Crypto Basics

NFTs Explained: What Are Non-Fungible Tokens?

A definitive guide to explain NFTs, or non-fungible tokens.
Token Metrics Team
7 minutes
MIN

NFTs, or non-fungible tokens, are gaining widespread popularity in the market for digital art and collectibles. In recent years, NFTs have become a cultural phenomenon, attracting the attention of crypto enthusiasts, digital art creators, and celebrities alike. As the Web 3.0 ecosystem continues to grow and adoption increases, many believe that NFTs will play a key role in the ownership of assets online.

So what are NFTs? Let's find out.

‍NFT Basics

NFTs, or non-fungible tokens, are a type of digital asset that represents ownership of something on the blockchain.

NFTs can be anything such as art, collectibles, music, profile pictures or PFP, DAO memberships, event tickets, gaming assets, virtual land, domain names, and so on. They can represent either completely digital assets or tokenized versions of assets that exist in the real world. Currently, there is a lot of excitement around using NFTs to sell virtual art.

Characteristics of NFTs

  • Ownership: NFT represents digital ownership of an item on a blockchain
  • Permanent: NFTs have data permanently stored within the token. This information includes images, messages, signatures, or any other data
  • Programmable: An NFT can be programmed to do anything. For example, an NFT artwork might be programmed to pay the artist royalties on every secondary sale of that artwork
  • Unique: NFTs are unique, and that uniqueness can be confirmed on a blockchain

How to Make an NFT

To create an NFT, or non-fungible token, you will need to first prepare your media file. NFTs can support a wide range of file types, including audio, images, and even 3D files. Some popular file types that are supported by NFTs include MP3, JPG, PNG, and GIF. You can also use 3D file formats like GLB to create NFTs that represent unique, digital objects.

Once your media is ready, you will need to set up a non-custodial wallet to securely store the cryptocurrency that you will use to buy, sell, and create NFTs. Non-custodial wallets are important because they allow you to retain control of your private keys, which are needed to access your cryptocurrency and make transactions. There are many different wallet options available, so it is important to do your research and choose one that is secure and user-friendly.

Once you have set up your wallet, you will need to buy Ethereum, or other fungible tokens depending on the blockchain being used, to cover the cost of minting your NFT. Ethereum is the most commonly used blockchain for NFTs, and it is typically the easiest to get started with. You can buy Ethereum using a variety of methods, including through a cryptocurrency exchange or from other individuals who are willing to sell.

Once you have your Ethereum, you will need to connect your wallet to an NFT marketplace like Rarible or OpenSea. These platforms allow you to easily create and mint your NFT, as well as trade and purchase NFTs created by others. To connect your wallet, simply tap the "Connect" button in the top right corner of the marketplace's website. This will create an account for you on the platform and allow you to begin creating your NFT.

To create your NFT, upload your media file to the platform and provide a description of your asset. You can choose to create a standalone piece, or create multiple NFTs of the same piece, each with its own unique characteristics. You can also set rules around royalties and other aspects of your NFT to ensure that you are fairly compensated for your work.

Once you are ready to mint your NFT, the process will require you to pay a small amount of ETH for transaction fees. This is necessary to get your NFT added to the blockchain and verified as unique. Once your NFT is minted, it will be available for trade and purchase on the marketplace. You can monitor the progress of your NFT and track its sales through your wallet or the marketplace's website.

NFT Secondary Markets

Creators make NFTs using blockchain-based minting platforms to retain more control over their creative output. Once NFTs are minted on a non-custodial wallet-compatible website, collectors and traders can sell these assets on the secondary market.

Here is a list of the most used NFT marketplaces:

  • OpenSea: OpenSea is the first and largest marketplace for NFTs. OpenSea is building tools that allow consumers to trade their items, creators to launch new digital works, and developers to build rich, integrated marketplaces for their digital items. It recently announced the support for Solana-based NFTs.
  • Coinbase NFT: Coinbase, a cryptocurrency exchange, recently launched its NFT marketplace in beta version to the public. This marketplace acts as a social media platform in which users can not only buy and sell NFTs but also interact with and showcase their collections using user profiles, likes, and comments.
  • Solanart: Solanart is the first and largest fully-fledged NFT marketplace on Solana. Users can get quick and easy access to digital collectibles, and explore, buy, and sell NFTs that run on the Solana blockchain.
  • Rarible: Rarible is a do-it-yourself NFT marketplace where you can mint NFTs when and how you please. Creators are highly favorable towards Rarible, as the minting process is free, easy, and unrestricted. Rarible’s native governance token “RARI” is used to incentivize platform users and give the community members a voice.
  • Nifty Gateway: Nifty Gateway is owned by the Gemini crypto exchange and has become one of the most known NFT marketplaces lately. They focus on viral drops from artists like Beeple, Trevor Jones, Pak, and more.
  • SuperRare: SuperRare (SR) is one of Ethereum’s debut crypto-art NFT marketplaces. Artists must be accepted to the platform before they can list their assets.

Notable NFT Projects

NFT-based companies have seen significant growth in recent years. Some notable examples include:

  • Yuga Labs: a blockchain technology company that creates Ethereum-based NFTs and digital collectibles. Yuga's most valuable NFT collection is Bored Ape Yacht Club, which has seen a floor price of over 150 ETH at its all-time high. In addition to apes, Yuga has also created dog NFTs, mutant apes, and deeds for its Metaverse. The company recently acquired Larva Labs, bringing high-value projects like Cryptopunks and Meebits under the Yuga brand. Yuga is backed by investors like Coinbase, Samsung, and Mark Cuban.
  • Doodles: a collection of 10,000 Ethereum-based NFTs created by artist BurntToast. The Doodles collection includes a wide range of visual traits, heads, costumes, and colorways. Owners of Doodles NFTs have exclusive access to new experiences like Space Doodles and Dooplicator.
  • Okay Bears: a collection of 10,000 Solana-based NFTs. Ownership of an Okay Bear grants access to a community of collectors and exclusive products, merchandise, and events.

Investing in NFTs

NFTs, or non-fungible tokens, provide many benefits as an investment vehicle.

One of the main advantages of NFTs is that they allow physical objects, such as artwork, to be tokenized.

Additionally, NFTs offer greater liquidity for investors, making it easier to trade and sell their assets.

The Future of NFTs

NFTs offer a new way to represent and prove ownership of assets on the blockchain.

This technology has already been used for digital art, collectibles, and in-game assets, but it has the potential to be applied to a wide range of other industries as well. For example, tokenized real estate could provide a way for people to invest in property without the barriers to entry that currently exist.

High-end fashion brands like Louis Vuitton have also expressed interest in using NFTs to track the ownership of luxury items.

Additionally, NFTs can be used to tokenize certifications, degrees, and licenses, providing a way to securely track and maintain this sensitive data on the blockchain.

Overall, the potential applications for NFTs are nearly limitless.

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A Complete Guide to Identifying the Best Crypto API for Your Project

Token Metrics Team
5
MIN

From real-time trading dashboards to AI-powered portfolio trackers, cryptocurrency APIs are the backbone of the modern digital asset ecosystem. Choosing the right API is essential for reliable data, robust functionality, and secure integration—but with dozens of options, where do you start?

Understanding Crypto APIs: What They Offer and Why They Matter

APIs, or Application Programming Interfaces, allow applications to communicate and exchange data efficiently. In the world of crypto, APIs provide access to blockchain data, real-time pricing, transaction history, market analytics, and much more. Their utility extends from simple balance checks to advanced trading bots and on-chain research tools.

  • Price Feeds: Get real-time and historical data on thousands of cryptocurrencies.
  • Trading Endpoints: Execute buy, sell, or transfer functions on connected exchanges (for eligible users).
  • On-chain Data: Analyze blockchain transactions, address activity, and smart contract interactions.
  • Analytics & Signals: Access AI-driven insights, technical analysis, and social sentiment.

Whether you’re a developer, researcher, or business building a crypto product, APIs enable you to integrate critical features without rebuilding from scratch.

Key Criteria for Selecting the Best Crypto API

No single API fits every use case. It’s important to evaluate potential providers using a structured set of criteria:

  1. Data Coverage: Does the API provide access to the assets, exchanges, or blockchains your project requires? Broader coverage reduces integration work.
  2. Reliability & Uptime: Financial applications demand high uptime and low latency. Look for published SLAs and transparent status pages.
  3. Data Freshness: For trading or analytics, real-time information (with second or sub-second granularity) is essential.
  4. API Documentation: Comprehensive, clear docs speed up development and reduce errors.
  5. Security: Encrypted endpoints, IP whitelisting, and robust authentication are musts when handling digital assets.
  6. Rate Limits & Pricing: Consider the volume of requests you expect and any associated costs if you scale.
  7. Advanced Analytics: Some APIs, like Token Metrics, offer AI-driven scores or unique signals—critical for edge use cases.

Using these filters helps ensure your selection is future-proof as the crypto landscape evolves.

Depending on your goals, you might need a mix of different API types. Here’s a breakdown of common categories and practical examples:

  • Market Data APIs: Used for displaying prices, volume, or market cap across apps, news sites, or bots. Example: Building a real-time crypto price widget using a data API.
  • Exchange APIs: Enable order execution, balance lookups, and trade history for integrated trading platforms. Example: Creating an automated trading bot that places orders on your behalf.
  • Blockchain APIs: Interact directly with multiple blockchains to query blocks, transactions, or events. Example: Monitoring smart contract events for a DeFi analytics dashboard.
  • Analytics & Signal APIs: Leverage AI or expert-curated signals to augment decision-making. Example: Using machine learning-powered API outputs for research or portfolio optimization tasks.

Carefully matching your use case to API type streamlines development and ensures better long-term results.

Evaluating API Documentation and Developer Support

Excellent documentation is the difference between a smooth integration and endless debugging. When reviewing API providers, consider:

  • Getting Started Guides: Step-by-step onboarding to authenticate, make your first call, and understand rate limits.
  • Code Samples: Access to ready-to-use examples in popular programming languages accelerates prototyping.
  • Community & Support Channels: Forums, Slack groups, and support tickets create a safety net for troubleshooting.
  • Status & Changelog: Transparent updates keep you aware of new features or breaking changes.

APIs with vibrant developer ecosystems—like those from Token Metrics and other major analytics platforms—tend to innovate and resolve issues quickly.

Security and Compliance Considerations for Crypto APIs

Security is paramount when accessing financial data and blockchain assets via APIs. Here’s how to assess providers:

  • Authentication Methods: Prefer token-based, OAuth, or similar secure approaches over legacy key mechanisms.
  • Encryption: Ensure endpoints are served over HTTPS with robust encryption standards.
  • Regulatory Alignment: While APIs themselves don’t provide investment advice, check if the provider follows relevant data privacy and security regulations.
  • Granular Permissions: Choose APIs that allow fine-grained access control (e.g., read-only vs. trading permissions).

A secure, compliant API minimizes operational and reputational risk as your project scales.

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

FAQs about Finding the Best Crypto API

What is a crypto API and why is it important?

A crypto API is a set of protocols allowing apps to access and interact with blockchain data, exchange prices, or trading functionality. It’s crucial for building reliable, scalable products in the digital asset space.

How do I compare different crypto APIs?

Compare APIs by assessing data coverage, documentation, security features, reliability, rate limits, advanced analytics, and pricing. Matching functionality to your use case is key to making the right choice.

Are there free crypto APIs available?

Yes, many providers offer free API tiers suitable for development and light use. However, higher request volumes or advanced features usually require a paid plan.

Do I need programming experience to use a crypto API?

Basic programming knowledge is recommended, as working with APIs often involves code. Some platforms provide low-code options or widgets for easier integration.

How can AI tools like Token Metrics improve my crypto research with APIs?

AI-driven platforms like Token Metrics can deliver actionable analytics, portfolio scores, and trend detection through easy-to-integrate APIs—empowering both individual and institutional researchers.

Disclaimer

This article is for informational and educational purposes only. It does not constitute investment, financial, or legal advice. Always independently verify data sources and API providers before integrating them into your projects.

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A Practical Guide to Using Crypto APIs for Your Next Project

Token Metrics Team
5
MIN

APIs have become the backbone of digital innovation, especially in the fast-paced world of cryptocurrencies. Whether you’re building analytics dashboards, powering trading bots, or simply retrieving up-to-date coin prices, understanding how to use crypto APIs is an essential skill for developers and data enthusiasts alike. This guide breaks down everything you need to know to get started and build effective solutions using crypto APIs.

What Is a Crypto API?

A crypto API (Application Programming Interface) is a set of digital tools and protocols that allows applications to communicate with cryptocurrency data sources such as exchanges, blockchains, or analytics platforms. With a well-designed API, developers can fetch real-time or historical market data, execute trades, review blockchain transactions, and tap into on-chain insights—all programmatically, without manual intervention. Common use cases for crypto APIs include portfolio tracking tools, market research dashboards, trading bots, and compliance monitoring systems.

Choosing the Right Crypto API for Your Project

There are several factors to consider when selecting a crypto API:

  • Data Coverage: Does the API provide the coins, tokens, exchanges, or blockchains you want to monitor or interact with?
  • Update Frequency: Certain applications, such as price alerts or trading bots, may require real-time data, while others function on hourly or daily updates.
  • API Limits and Pricing: Most APIs offer free tiers with rate limits. If you need scalable, high-frequency access, review the pricing and quota model.
  • Reliability and Uptime: Opt for APIs with well documented uptime records and responsive support.
  • Security Features: Look for secure authentication, encrypted endpoints (HTTPS), and, when applicable, permissions-scoped API keys.
  • Advanced Features: Some APIs, such as the Token Metrics API, provide AI-driven trading signals, analytics, and on-chain insights alongside standard market data.

Examples of popular crypto APIs include CoinGecko, CryptoCompare, Binance API, and specialized analytics APIs like Token Metrics.

Getting Started with Crypto APIs: Step-by-Step

Once you've selected a crypto API, follow these general steps to integrate and use it:

  1. Register for Access: Most platforms require setting up an account and generating an API key—a unique credential that authorizes your app to access the API’s endpoints.
  2. Read the Documentation: Study endpoint details, request/response formats, authentication methods, and examples provided by the API provider.
  3. Make Your First Request: Use tools like curl, Postman, or your programming language’s HTTP library to send your first test request. For example, fetching the latest BTC/USD price is a common starting point.
  4. Handle API Responses: APIs usually return data in JSON or XML. Parse and validate this data in your application, handling errors and timeouts gracefully.
  5. Integrate Advanced Features: As you grow comfortable, start leveraging advanced endpoints: on-chain analytics, trading signals, wallet balances, or historical trends.
  6. Monitor and Maintain: Implement retries, caching, and error logging. Monitor your API usage against any rate limits to ensure uninterrupted service.

By starting with a specific analytic or automation goal, then systematically expanding feature use as you learn, you can steadily build robust crypto-powered tools.

Crypto API Security and Best Practices

Handling financial and market data demands heightened attention to security. Adhere to these best practices when using any crypto API:

  • Never hardcode API keys into publicly visible code repositories. Use environment variables or secure credentials managers.
  • Apply Principle of Least Privilege: If the API supports scopes, request only the permissions your app actually needs.
  • Use HTTPS Only: Always connect to APIs over encrypted HTTPS endpoints. Avoid APIs that do not offer secure connections.
  • Regularly Rotate Keys: Change your API keys periodically and immediately if you suspect compromise.
  • Audit Third-Party Packages: When working with open-source crypto libraries to process API data, verify their reputation and maintenance status.
  • Monitor Usage: Use analytics dashboards to detect abnormal usage patterns, which can indicate bugs or attempted abuse.

Following these protocols can help safeguard your application—and in some scenarios, sensitive wallet or trading information—from common vulnerabilities.

Real-World Use Cases for Crypto APIs

Crypto APIs are used across a spectrum of industries and applications, including:

  • Trading Bots: Automated agents that respond to market movements based on preset rules or AI-based strategies.
  • Market Research Platforms: Aggregating and visualizing market data, sentiment analysis, and key performance indicators for institutional analysts or retail users.
  • Wallet and Portfolio Apps: Displaying holdings, transaction histories, and P&L by pulling blockchain and price data from multiple APIs.
  • Compliance and KYC Applications: Monitoring transactions and addresses for regulatory adherence and anomaly detection.
  • AI-Based Signal Services: Delivering advanced analytics and trade signals by consuming data from multiple API sources, such as those offered by Token Metrics.

As both crypto and AI technologies continue to advance, the synergy between API-driven data and algorithmic analysis promises even more powerful applications, from DeFi monitoring to predictive analytics and risk management.

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

Frequently Asked Questions: Crypto APIs

How do I choose the best crypto API?

Start by defining your data needs—crypto coverage, real-time vs. historical data, and reliability. Compare options by uptime, security, advanced features (like analytics), and cost structure.

Can I use multiple APIs in one project?

Yes. Many developers aggregate data from different APIs to improve coverage or redundancy, but be mindful of integration complexity and API key management.

Are crypto API keys secure?

API keys provide basic access control, but their security depends on your management—keep them secret, never expose publicly, and rotate regularly.

Do I need to know programming to use crypto APIs?

Most crypto APIs are designed for developers, but many tools and platforms let you use APIs with minimal coding. However, basic programming helps unlock their full power.

What can I build using crypto APIs?

APIs power trading bots, data dashboards, portfolio trackers, analytics platforms, research tools, compliance monitoring, and AI-driven crypto agents—the possibilities expand with market needs.

Disclaimer

This article is for educational purposes only. It does not provide investment advice, trading recommendations, or endorsements. Token Metrics and its authors make no representations regarding the accuracy or suitability of information herein.

Research

How to Choose the Best Crypto API for Your Project Needs

Token Metrics Team
6
MIN

Building crypto-powered apps, analytical dashboards, or AI trading bots? The backbone of your solution is the API you choose. With dozens of crypto APIs—each promising deep data, speed, and reliability—it’s challenging to determine which is truly best for your development goals. This guide breaks down what to look for in a crypto API, compares leading providers, and offers insights for startups, researchers, and enterprises alike.

What Is a Crypto API? Key Fundamentals

At its core, a crypto API (Application Programming Interface) allows apps, platforms, or AI agents to fetch and interact with real-time or historical blockchain and cryptocurrency data. APIs are the bridge between raw blockchain data and accessible, actionable information such as:

  • Live and historical prices for Bitcoin, Ethereum, and thousands of tokens
  • Trading volumes, liquidity, and order book depth
  • Wallet addresses, balances, and transaction histories
  • On-chain analytics (e.g., token flows, wallet behavior)
  • Market signals and sentiment indicators

Some crypto APIs specialize in data aggregation from exchanges, others in blockchain indexing, and some combine both along with AI-driven insights. Understanding your use case—be it price feeds, portfolio management, compliance, or research—is the first step towards choosing the best fit.

How to Evaluate Crypto APIs: Key Criteria

Not all crypto APIs are created equal. Before integrating one into your stack, consider these critical factors:

  • Data Coverage: Does the API cover all required assets (spot, derivatives, DeFi tokens, NFTs)? Is the data sourced from top exchanges and direct blockchain nodes?
  • Real-Time Speed: For trading or risk management, sub-second data delivery is essential. Check latency and WebSocket support.
  • Historical Depth: Does it offer deep historical price, trade, and on-chain datasets for backtesting or research?
  • Reliability & Uptime: Review the provider’s SLA, downtime history, and incident transparency.
  • Scalability & Rate Limits: Is there throttling for large requests? Do paid tiers allow programmatic access at enterprise scale?
  • Developer Experience: Look for clear docs, SDKs, sample code, and active support channels.
  • Compliance: Especially for wallets and analytics platforms, look for APIs with robust KYC/AML integrations and compliance monitoring.
  • Pricing & Free Tier: Is there a free plan? Are paid tiers transparent and cost-effective as you scale?

Comparing Leading Crypto APIs: Features and Use Cases

Several platforms dominate the crypto API landscape, each with specific strengths. Below is an overview of top contenders, their focus areas, and ideal users:

  • Token Metrics API: Combines real-time prices, advanced trading signals, portfolio analytics, and on-chain intelligence. Applications include AI trading bots, investment dashboards, and research automation platforms.
  • CoinGecko & CoinMarketCap APIs: Widely used for price tracking and market cap data with broad asset coverage. Ideal for charts, tickers, and casual portfolio apps.
  • CryptoCompare API: Deep market data aggregation, including historical tick-level trades; popular in financial research and analytics.
  • Glassnode API: Specialized in on-chain metrics, network activity, wallet behavior, and blockchain health indicators—best for advanced research platforms.
  • Alchemy & Infura: Focused on blockchain node APIs for Ethereum and major chains, catering to dApp, DeFi, and NFT builders needing raw blockchain data instead of market metrics.

Choosing among these providers often depends on your feature needs. For example, if AI or automated decision-making is a focus, APIs that blend price data with AI-powered analytics (like Token Metrics) can deliver an edge in user experience and automation.

Crypto API Use Cases: From AI Agents to Market Analytics

The best crypto API isn’t about “most data”—it’s about empowering your application’s mission. Consider these scenarios:

  • AI Trading Bots: Need ultra-fast, reliable price feeds and actionable trading signals. Advanced APIs may offer predictive models or backtesting endpoints.
  • DeFi Dashboards: Require smooth aggregation of tokens, protocols, and wallet stats across chains for users to see full portfolio health.
  • On-Chain Analytics Platforms: Benefit from direct blockchain indexing, whale monitoring, and network health metrics.
  • Compliance & Forensics: Must access KYC data integrations, transaction tracing, and suspicious activity monitoring.
  • Mobile Apps or Widgets: Favor easy integration, robust documentation, and manageable rate limits for smooth UX.

Emerging AI-powered APIs, exemplified by providers like Token Metrics, now also deliver sentiment analysis, predictive signals, and on-chain behavior analytics useful for both retail and institutional developers.

Selecting and Implementing Your Ideal Crypto API: Best Practices

Narrowing your options comes down to testing—and future-proofing your build:

  1. Test Multiple APIs: Use free keys to compare performance, latency, and error rates in your environment.
  2. Plan for Scale: Consider how the API provider’s pricing, rate limits, and support will adapt as your user base grows.
  3. Prioritize Security: Evaluate authentication, encryption, and documentation for secure API usage.
  4. Monitor Continuously: Even reliable APIs can experience downtime. Use monitoring tools and set up alerts for performance issues.
  5. Explore AI Enhancements: Where possible, integrate APIs with embedded AI or analytics for a smarter, more adaptive user experience.

Ultimately, the “best” crypto API aligns not only with your current requirements but also provides extensibility for tomorrow’s market innovations and compliance standards.

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

Frequently Asked Questions About the Best Crypto APIs

What types of data can I access with a crypto API?

Crypto APIs offer a range of data, including real-time prices, historical charts, trading volumes, blockchain transactions, wallet activity, and often on-chain or sentiment analytics. Some also provide trading signals, DeFi protocol data, or NFT analytics based on their focus.

Are crypto APIs safe to use in production apps?

Reputable API providers use encrypted connections and secure authentication. However, it's essential to follow best practices, such as keeping keys private, monitoring usage, and using robust error handling to ensure security and uptime.

Can I get a free crypto API key for development?

Most leading providers (including Token Metrics, CoinGecko, and CoinMarketCap) offer free API tiers ideal for prototyping or hobby projects, though limits may apply to request rates or data depth. Always review free versus paid feature lists before scaling.

Which crypto API is best for AI trading bots?

APIs that deliver both low-latency price feeds and AI-powered signals—like the Token Metrics API—can enhance the performance and intelligence of AI trading bots. Choose based on the depth of data and analytics you require.

How do I switch between crypto APIs if my needs change?

Abstracting API integration in your codebase (using middleware or SDKs) makes it easier to swap providers if needed. Always review new documentation for compatibility, endpoints, and rate limits when transitioning.

Disclaimer

This article is for informational and educational purposes only. It does not constitute investment advice or an endorsement of any provider or service. Always conduct independent technical and compliance review before integrating any third-party API.

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