Crypto Basics

What is a Hard Fork and How Does it Work?

Discover what a hard fork is and how it works in blockchain technology. Learn about its impact and implementation in this comprehensive guide
S. Vishwa
5 Minutes
MIN

In the world of blockchain technology, a hard fork refers to a significant and radical change in a network's protocol. This change results in the creating of two separate branches, one following the previous protocol and the other following the new version. 

Unlike a soft fork, which is a minor upgrade to the protocol, a hard fork requires all nodes or users to upgrade to the latest version of the protocol software.

Understanding Blockchain and Forks

Before delving into hard forks, it's important to understand the basics of blockchain technology. A blockchain is a decentralized digital ledger that records transactions and other events in a series of blocks. 

Each block contains data and a set of instructions, known as protocols, which dictate how the blockchain network functions. Because a blockchain is decentralized, any changes to its protocol need to be voted on and approved by its community of users. 

When developers propose major changes or disagreements arise regarding the development of a blockchain, a hard fork may be initiated to create a new and separate blockchain.

How Does a Hard Fork Work?

When a hard fork occurs, the new version of the blockchain is no longer compatible with older versions. This creates a permanent divergence from the previous version of the blockchain. 

The new rules and protocols implemented through the hard fork create a fork in the blockchain, with one path following the upgraded blockchain and the other path continuing along the old one.

Miners, who play a crucial role in verifying transactions and maintaining the blockchain, must choose which blockchain to continue verifying. Holders of tokens in the original blockchain will also be granted tokens in the new fork. 

However, it's important to note that the old version of the blockchain may continue to exist even after the fork, potentially with security or performance flaws that the hard fork aimed to address.

Reasons for Hard Forks

Developers may implement a hard fork for various reasons. One common motivation is to correct significant security risks found in older versions of the software. 

Hard forks can also introduce new functionality or reverse transactions, as seen in the case of the Ethereum blockchain's hard fork to address the hack on the Decentralized Autonomous Organization (DAO).

In 2016, the Ethereum community unanimously voted in favor of a hard fork to roll back transactions that resulted in the theft of millions of dollars worth of digital currency. 

The hard fork allowed DAO token holders to retrieve their funds through a newly created smart contract. While the hard fork did not undo the network's transaction history, it enabled the recovery of stolen funds and provided failsafe protection for the organization.

Examples of Hard Forks

Hard forks have occurred in various blockchain networks, not just in Bitcoin. Bitcoin itself has witnessed several notable hard forks. 

In 2014, Bitcoin XT emerged as a hard fork to increase the number of transactions per second that Bitcoin could handle. However, the project lost interest and is no longer in use.

Another significant hard fork in the Bitcoin ecosystem took place in 2017, resulting in the creation of Bitcoin Cash. 

The hard fork aimed to increase Bitcoin's block size to improve transaction capacity. Subsequently, in 2018, Bitcoin Cash experienced another hard fork, leading to the emergence of Bitcoin Cash ABC and Bitcoin Cash SV.

Ethereum, another prominent cryptocurrency, also underwent a hard fork in response to the DAO hack mentioned earlier. The fork resulted in the creation of Ethereum Classic, which maintained the original blockchain and the updated Ethereum network.

Pros and Cons of Hard Forks

Hard forks offer several benefits to blockchain networks. They can address security issues, enhance the performance of a blockchain, and introduce new features or functionalities. 

Hard forks also provide an opportunity for participants in a blockchain community to pursue different visions for their projects and potentially resolve disagreements.

However, hard forks also come with disadvantages. They can confuse investors when a new but similar cryptocurrency is created alongside the original. 

Furthermore, hard forks may expose blockchain networks to vulnerabilities, such as 51% attacks or replay attacks. Additionally, the existence of the old version of the blockchain after a hard fork may lead to security or performance flaws that the fork aimed to fix.

Hard Forks vs. Soft Forks

While hard forks create two separate blockchains, soft forks result in a single valid blockchain. In a soft fork, the blockchain's existing code is updated, but the old version remains compatible with the new one. 

This means that not all nodes or users need to upgrade to the latest version of the protocol software. The decision to implement a hard fork or a soft fork depends on a blockchain network's specific goals and requirements. 

Hard forks are often favored when significant changes are necessary, even if a soft fork could potentially achieve the same outcome.

Conclusion

Hard forks play a significant role in the evolution of blockchain technology. They allow for radical changes to a network's protocol, creating new blockchains and potential improvements in security, performance, and functionality. 

However, hard forks also come with risks and challenges, such as confusion among investors and possibly exposing blockchain networks to vulnerabilities.

As the blockchain industry continues to evolve, it's essential for investors and stakeholders to stay informed about proposed changes and forks in their cryptocurrency holdings. 

Understanding the implications of hard forks and their potential impact on the value of crypto assets is crucial for navigating this rapidly changing landscape.

Remember, investing in cryptocurrency should be cautiously approached, especially for newcomers who are still learning how blockchain works. Stay updated, do thorough research, and seek professional advice before making investment decisions.

Disclaimer

The information provided on this website does not constitute investment advice, financial advice, trading advice, or any other advice, and you should not treat any of the website's content as such.

Token Metrics does not recommend buying, selling, or holding any cryptocurrency. Conduct your due diligence and consult your financial advisor before making investment decisions.

Build Smarter Crypto Apps &
AI Agents in Minutes, Not Months
Real-time prices, trading signals, and on-chain insights all from one powerful API.
Grab a Free API Key
Token Metrics Team
Token Metrics Team

Recent Posts

Research

Top Programming Languages for Working with Crypto APIs

Token Metrics Team
6
MIN

As the crypto ecosystem expands, APIs are the bridge connecting developers to real-time prices, blockchain data, and decentralized tools. Choosing the right programming language is critical—whether you're building trading bots, portfolio trackers, or AI research agents for digital assets. How do you select the most effective language for working with crypto APIs? Let's break down the options, trade-offs, and best practices for developers entering this dynamic space.

Python: The Leading Choice for Crypto APIs

Python stands out as the top choice for many developers building crypto-powered applications. Its simple syntax, robust standard libraries, and thriving open-source community have propelled it to the forefront of blockchain and crypto development. Here's why:

  • Extensive library support: Powerful packages such as requests, web3.py, and ccxt simplify everything from basic REST calls to advanced blockchain and exchange integrations.
  • AI and data science integration: Python's dominance in AI and machine learning (through libraries like TensorFlow and scikit-learn) makes it ideal if you want to combine crypto market data with analytics or modeling.
  • Rapid prototyping: Python's readability increases development speed, allowing teams to quickly test new crypto strategies or data queries.
  • Strong community and documentation: There are abundant tutorials and prebuilt modules for most major exchanges and blockchains, lowering the entry barrier for newcomers.

Python is especially popular for backend services, trading bots, analytics dashboards, and AI-driven crypto research platforms. Its versatility makes it an excellent starting point for most crypto API projects.

JavaScript and Node.js: For Both Web and Backend

JavaScript's ubiquity in web development—and the rise of Node.js for backend—have cemented its importance in the crypto API landscape. Here's why developers favor JavaScript:

  • Full-stack flexibility: With frameworks like React or Vue.js on the frontend, and Node.js on the backend, developers can seamlessly create interactive dApps and dashboards that communicate with blockchain or exchange APIs.
  • Real-time capabilities: Libraries like web3.js make it easy to connect web applications directly to Ethereum and other blockchains, powering features like wallet integration and token swaps.
  • Growing DeFi ecosystem: Many decentralized finance (DeFi) products and Web3 tools have rich JavaScript or TypeScript SDKs for easy adoption.
  • Strong community: JavaScript's vast ecosystem ensures that support is available for integrating most major crypto APIs, whether for simple price data or advanced smart contract interactions.

JavaScript and Node.js are top picks for projects focused on user-facing dashboards, live trading interfaces, and dApp development where real-time interaction is crucial.

Compiled Languages: Go, Java, and C#

For developers who prioritize performance and scalability, compiled languages like Go, Java, and C# come into play:

  • Go (Golang): Known for its concurrency support and efficiency, Go is popular for blockchain node clients (e.g., Ethereum's Geth) and high-throughput servers that need to process large amounts of real-time crypto data via APIs. Its static typing helps reduce runtime errors, and its small binaries make deployment easy.
  • Java: Java remains a leading choice in enterprise environments where reliability and security are paramount. Java powers several blockchain SDKs (such as BitcoinJ) and is often favored for building robust backend crypto services.
  • C#: Particularly useful for Windows-based environments and gaming platforms leveraging blockchain assets. Libraries like NBitcoin enable smooth API integration with Bitcoin and related networks.

While these languages often require more boilerplate and steeper learning curves than Python or JavaScript, they excel in situations where uptime, parallel processing, and performance are vital.

Smart Contract and Blockchain-Specific Languages: Solidity & Rust

When your project needs to interact deeply with blockchain networks beyond just APIs—such as deploying smart contracts or working at the protocol level—specialized languages become essential:

  • Solidity: The dominant language for Ethereum smart contracts, Solidity is essential for developers building and querying contracts directly. While typically not used to interact with APIs, it's often complemented by Python (web3.py) or JavaScript (web3.js) scripts that handle API calls and contract interactions together.
  • Rust: Fast rising in popularity, Rust powers next-gen blockchains like Solana and Near. Its emphasis on memory safety and concurrency makes it ideal for performance-critical crypto platforms. Rust also supports tooling for building high-speed client libraries and backend services that consume blockchain APIs.

For API-focused projects, these languages play a role primarily when paired with a more general-purpose language (like Python or JavaScript) for off-chain tasks, with the specialized code handling on-chain logic.

Factors to Consider When Choosing a Language for Crypto APIs

The ideal programming language depends on a few project-specific factors:

  • Project type: Analytics and research tools often favor Python; user-facing platforms lean towards JavaScript/Node.js; and mission-critical applications may benefit from Go or Java.
  • API documentation and libraries: Mature APIs will have client libraries in popular languages. Libraries like Token Metrics API, Binance, or Coinbase typically support Python, JavaScript, and Java.
  • Security considerations: Languages with clear type systems and strong error handling (like Rust and Go) may reduce API integration risks.
  • Team expertise: Leverage your team’s current language strengths to minimize onboarding time and maximize productivity.
  • Ecosystem support: Evaluate how active the language’s crypto developer community is for support and ongoing maintenance of crypto API wrappers or SDKs.

Ultimately, the best crypto API projects balance technical strengths, developer proficiency, and the support network a programming language provides.

Build Smarter Crypto Apps & AI Agents with Token Metrics

Token Metrics provides real-time prices, trading signals, and on-chain insights all from one powerful API. Grab a Free API Key

Is Python better than JavaScript for working with crypto APIs?

Both Python and JavaScript are leading choices. Python excels for backend analytics and AI-driven tools, while JavaScript is often used for building interactive dApps and web interfaces directly leveraging APIs. The right choice often depends on your application requirements and team expertise.

What libraries can help integrate APIs in crypto apps?

Popular libraries include web3.py and ccxt for Python, web3.js and ethers.js for JavaScript, as well as client SDKs provided by leading exchanges and data providers. Token Metrics also offers a powerful API for market data and analytics.

How can I enhance API security in crypto projects?

Use secure API key management, implement rate limiting, utilize HTTPS for data transmission, and validate all external responses. Choosing a strongly-typed language (like Go or Rust) and leveraging well-maintained libraries can reduce vulnerabilities.

Should I learn Solidity or Rust for API development?

Solidity and Rust are best suited for smart contract and protocol-level blockchain work—not direct API integration. For most API-driven crypto projects, Python, JavaScript, or Go are more practical; learn Solidity or Rust if you plan to develop on-chain logic or new blockchain platforms.

How does Token Metrics support developers working with crypto APIs?

Token Metrics delivers AI-driven crypto analytics and signals via a unified API, empowering developers to build research, trading, or analytical tools rapidly. The platform provides robust documentation and versatile endpoints compatible with major programming languages.

Disclaimer

This content is for informational and educational purposes only. It does not constitute investment, financial, or legal advice. Use all programming languages, APIs, and crypto tools at your own risk and always conduct thorough technical due diligence before integrating third-party services or tools into your projects.

Research

A Practical Guide to Integrating a Crypto API into Your App or Website

Token Metrics Team
6
MIN

Cryptocurrency continues to reshape digital finance, but harnessing its potential in your apps or websites starts with reliable data and functional integrations. Whether you’re building a trading dashboard, NFT platform, or analytics tool, crypto APIs can help your users interact with blockchain data in real time. But what exactly is involved in integrating a crypto API, and which best practices should developers follow to ensure security and scalability?

What Is a Crypto API?

A crypto API (Application Programming Interface) enables your application to access blockchain data—such as prices, market statistics, trading signals, wallets, or transactions—without running a full node. These APIs expose services from exchanges, data aggregators, or specialized blockchain infrastructure providers, offering an efficient way for developers to query real-time or historical information about one or many cryptocurrencies.

Key types of crypto APIs include:

  • Market Data APIs: Deliver up-to-date price, volume, and order book data from multiple exchanges.
  • Trading APIs: Enable trade execution, portfolio monitoring, and account management on supported platforms (requires authentication).
  • Blockchain Explorer APIs: Fetch detailed wallet, block, and transaction data directly from public blockchains.
  • On-chain Analytics APIs: Provide insights into address activity, token flows, and DeFi metrics for smarter analysis and research.

Steps to Integrate a Crypto API Into Your App or Website

Integration complexity depends on your project’s requirements, the data you need, and your tech stack. Below is a streamlined process you can follow:

  1. Identify Your Use Case: Define whether you need price feeds, transaction history, wallet data, or on-chain analytics. This will narrow down your API options.
  2. Choose a Reputable API Provider: Compare providers based on documentation clarity, data coverage, latency, uptime, security, and cost. Leading options include Token Metrics API, CoinGecko, CoinMarketCap, Alchemy (for blockchain data), and others.
  3. Register for an API Key: Most APIs require authentication via a key. Signing up typically takes minutes and often involves picking a free or paid plan depending on volume needs.
  4. Study Documentation and SDKs: Review API endpoints, request/response models, limits, and code samples. Many providers offer SDKs and libraries for popular languages like Python, JavaScript, and Java.
  5. Integrate Into Your App: Use HTTP requests (REST or WebSocket) on the backend or frontend. Always keep API keys secure (never expose them client-side in public apps).
  6. Handle Responses and Edge Cases: Validate all incoming data before displaying or using it. Implement error handling for issues like rate limits, network errors, or service downtime.
  7. Monitor Usage and Optimize: Track API consumption and response times. As your app grows, consider caching strategies or upgrading your plan for higher throughput.

With new blockchain protocols and DeFi innovations, crypto APIs serve a growing variety of development scenarios, including:

  • Real-Time Market Dashboards: Aggregate live crypto asset prices, volumes, and charts for traders and investors.
  • Portfolio Trackers: Show users up-to-date balances and value changes on connected wallets or exchange accounts.
  • Token Price Alerts: Trigger notifications based on user-defined price movements or market signals.
  • Analytics and Research Tools: Provide on-chain metrics, sentiment analysis, or token scoring using APIs offering deeper analytics.
  • Decentralized Apps (DApps): Power smart contracts, DeFi analytics, or NFT galleries with blockchain state data.

Security Best Practices for Crypto API Integration

Integrating financial APIs brings unique security and privacy considerations. To safeguard both your application and its users, adopt the following best practices:

  • Keep API Keys Private: Store keys in secure backends or environment variables. Never hard-code secrets or expose them in browser-side code.
  • Enforce Least Privilege: Only request the minimum data and permissions needed for your use case.
  • Use HTTPS Endpoints: Always communicate over secure channels to prevent exposure of risk-sensitive data.
  • Validate and Sanitize Data: Carefully check all incoming data for integrity and format before processing in your app.
  • Monitor for Abuse or Anomalies: Track API activity, control rate limits, and be alert for suspicious behavior or excessive usage.

Measuring Quality and Performance of Crypto APIs

Not all crypto APIs are built the same. To ensure seamless user experience and reliability for your app or site, regularly assess:

  • Uptime and Latency: Higher uptime and low latency mean data is available when you need it most, especially for trading or arbitrage applications.
  • Data Breadth and Accuracy: Choose APIs that cover the assets, exchanges, and protocols relevant to your target audience—and that keep up with rapid market evolution.
  • Support and Documentation: Responsive support teams and thorough documentation can save substantial development time and headaches.
  • Scalability: As your application scales, verify that your API can handle increased load without causing bottlenecks or failing to deliver data on time.

Build Smarter Crypto Apps & AI Agents with Token Metrics

Token Metrics provides real-time prices, trading signals, and on-chain insights all from one powerful API. Grab a Free API Key

FAQ: Integrating Crypto APIs Into Apps and Sites

What programming languages can I use with crypto APIs?

Most crypto APIs are RESTful and language-agnostic. Popular options include JavaScript (Node.js), Python, Java, Ruby, Go, and C#. Many providers also supply SDKs for quick setup in these languages.

Are there free crypto API options available?

Yes, many crypto API providers, including Token Metrics, offer free tiers with rate limits suitable for development and testing. For production workloads or higher request volume, upgrading may be necessary.

Can I use a crypto API for real-time trading?

Some APIs allow trade execution and position monitoring, but this requires authentication and additional security considerations. Always follow platform-specific restrictions and compliance requirements when handling trading actions.

How do I choose the best crypto API for my app?

Evaluate APIs based on the data scope, latency, documentation quality, scalability, pricing, and available features such as on-chain analytics or advanced trading signals. Community reviews and support responsiveness are also important factors.

Is integrating crypto APIs secure?

API integration can be secure if you use HTTPS, safeguard your API keys, validate all inputs and outputs, and regularly monitor application and network activity. Following best practices and choosing reputable providers is crucial.

Disclaimer

This article is for informational purposes only. It does not provide investment advice, guarantees of accuracy, or endorse any specific technology, protocol, or strategy. Always conduct your own technical and security due diligence before integrating any third-party services.

Research

How Crypto APIs Empower Effortless Portfolio Tracking

Token Metrics Team
6
MIN

As the digital asset ecosystem grows more complex, keeping tabs on multiple cryptocurrencies across wallets, exchanges, and DeFi protocols can feel overwhelming. Many crypto enthusiasts and data-driven researchers are turning to APIs—powerful tools that automate and streamline portfolio tracking. But how exactly do crypto APIs help you monitor your digital assets, and what should you know before getting started?

What Is a Crypto API and Why Use One?

An API, or Application Programming Interface, acts as a bridge allowing software programs to communicate with one another. In the context of cryptocurrency, crypto APIs provide standardized and secure access to real-time and historical blockchain data, market prices, account balances, transaction history, and more.

Using a crypto API for portfolio tracking means you can:

  • Automatically aggregate holdings from multiple wallets or exchanges.
  • Monitor portfolio value with up-to-date price data.
  • Analyze allocations, performance, and exposure across assets and chains.
  • Integrate insights into custom dashboards, spreadsheets, or research tools.
For developers and power users, APIs unlock the potential for sophisticated workflows, real-time notifications, and integration with AI-driven analytics solutions.

How Crypto APIs Track Your Portfolio

Most portfolio tracking APIs fall into one or more of these categories:

  • Exchange APIs: Connect directly to trading platforms to fetch balances, trade history, and transaction data.
  • Blockchain Explorer APIs: Query public blockchains (like Ethereum, Bitcoin) to track wallet balances or specific transactions via address lookup.
  • Aggregators: Combine data from multiple sources (exchanges, wallets, DeFi apps) to offer a comprehensive, unified portfolio overview.
  • Analytics & On-chain Insights: Advanced APIs like Token Metrics layer research, trading signals, and on-chain data onto portfolio monitoring for deeper analysis.

To use these APIs, you typically generate an API key from the provider, configure access permissions (like read-only for safety), and then supply your wallet addresses or connect exchange accounts. Data is returned in machine-readable formats such as JSON, making it easy to feed into portfolio apps, visualization dashboards, or research workflows.

Benefits and Limitations of API-Based Portfolio Tracking

Using crypto APIs for portfolio tracking offers several key advantages:

  • Automation: Eliminate manual tracking and data entry errors.
  • Real-time Accuracy: Reflect the latest price and wallet balance changes.
  • Custom Integration: Tailor insights for your preferred workflow or platform.
  • Enhanced Analysis: Combine price, transaction, and on-chain data for deeper research.

However, APIs also come with practical limitations:

  • Technical Complexity: Requires some programming knowledge or use of pre-built tools.
  • Rate Limits: Providers may cap the number of requests per minute or day.
  • Security Considerations: Sharing exchange API keys or wallet addresses demands careful management of permissions and privacy.
  • Incomplete Data: Not all exchanges or blockchains are supported by every API.

Making sure your chosen API covers your required assets, chains, and platforms is crucial for effective portfolio monitoring.

How to Get Started with Crypto Portfolio APIs

If you’re interested in automating your portfolio tracking with a crypto API, the following workflow is a common approach:

  1. Identify Your Needs: Determine which sources (exchanges, wallets, chains) and data (balances, historical prices) you want to monitor.
  2. Select a Reputable API Provider: Review offerings like Token Metrics and compare available endpoints, asset coverage, update frequency, and security features.
  3. Register for API Access: Sign up for an account and obtain your API key(s). Configure permissions such as read-only portfolio data where possible.
  4. Implement or Integrate: Use code libraries or third-party portfolio apps that support your chosen API, or build a custom integration to display data in spreadsheets, dashboards, or analysis tools.
  5. Test Security and Accuracy: Validate that data is being pulled securely and accurately reflects your portfolio—including regular reviews of API permissions.

You don’t need to be a developer to benefit—many plug-and-play crypto tracking apps are built atop APIs, letting anyone leverage automated monitoring.

AI and the Next Generation of Crypto Portfolio APIs

The evolution of crypto APIs has accelerated with the rise of AI-powered analytics, creating opportunities to go beyond tracking simple balances. Platforms such as Token Metrics use machine learning to identify potential patterns in on-chain flows, provide portfolio exposure metrics, and surface unusual trading activity.

For quantitative traders, developers, and researchers, combining APIs with AI agents enables:

  • Automated alerts for risk and performance thresholds.
  • Portfolio rebalancing models based on on-chain and market signals.
  • Aggregated intelligence—such as sector allocations, historical returns, and on-chain wallet behaviors—delivered directly into research dashboards.
Ultimately, integrating AI and crypto APIs can result in a more holistic, dynamic approach to managing digital assets, offering valuable context for informed tracking and analysis.

Build Smarter Crypto Apps & AI Agents with Token Metrics

Token Metrics provides real-time prices, trading signals, and on-chain insights all from one powerful API. Grab a Free API Key

FAQ: Crypto APIs for Portfolio Tracking

What is a crypto API?

A crypto API is a software interface that allows applications or users to access and retrieve cryptocurrency data—such as balances, prices, trades, or transactions—from exchanges, blockchains, and data aggregators in real time.

Are crypto APIs secure to use for tracking my portfolio?

Most reputable APIs use strong security measures. For exchange APIs, set read-only permissions when possible, and never share your private keys. Always review a provider's documentation and best practices before use.

Can I use crypto APIs without coding skills?

While coding offers maximum flexibility, many portfolio tracking platforms and apps utilize APIs behind the scenes to collect and display your asset data—no coding required.

What’s the difference between using a crypto API and a portfolio tracking app?

APIs are tools for collecting and sharing data, often requiring custom setup, while apps are ready-made solutions built on APIs for ease of use. Advanced users might use APIs directly for custom or automated tracking; others may prefer user-friendly apps.

Does Token Metrics offer a crypto portfolio API?

Yes. Token Metrics provides a dedicated API offering real-time prices, trading signals, and on-chain analytics that can be used for portfolio tracking and research. Refer to their documentation for integration steps.

Disclaimer

This content is for educational and informational purposes only. It does not constitute investment, financial, or trading advice. Token Metrics does not guarantee or warrant any results or third-party services mentioned herein. Always conduct your own research before using new technologies or services in your crypto workflow.

Choose from Platinum, Gold, and Silver packages
Reach with 25–30% open rates and 0.5–1% CTR
Craft your own custom ad—from banners to tailored copy
Perfect for Crypto Exchanges, SaaS Tools, DeFi, and AI Products