Research

Top Free APIs Every Developer Should Know in 2024

Discover the best free-to-use APIs for crypto, AI, and data apps. See which trusted APIs developers rely on for robust features, reliability, and easy integration.
Token Metrics Team
5
MIN

APIs are the silent workhorses powering today’s most innovative software. Whether you’re a crypto enthusiast automating portfolio analysis, or a web developer looking to enrich your app with real-time data, the right free API can supercharge your project—and your productivity. But with thousands out there, which free APIs truly stand out for reliability, ease of use, and breadth of features?

Why Free APIs Matter for Developers and Innovators

APIs—Application Programming Interfaces—allow applications to seamlessly interact, share insights, and build on each other's strengths. The best free-to-use APIs democratize access to powerful datasets, functionalities, and market signals. For crypto, AI, fintech, or simply creative digital projects, high-quality APIs can:

  • Accelerate product development with ready-made data and processing tools
  • Enable experiments in new tech areas without initial investment
  • Foster community-driven innovation thanks to open documentation and easy onboarding

However, not all free APIs are created equal. Some offer limited usage tiers, outdated data, or spotty reliability. That’s why informed selection is crucial, especially for mission-critical apps.

Top Free APIs for Cryptocurrency and Blockchain Projects

The crypto landscape thrives on transparency and timely data. For enthusiasts building bots, dashboards, or research tools, these free APIs consistently earn praise:

  • CoinGecko API: Delivers comprehensive token prices, volumes, and market data. Free tier includes generous rate limits and supports thousands of assets.
  • CoinMarketCap Public API: Offers price feeds and historical data for cryptocurrencies, ideal for analysts and monitoring tools.
  • Etherscan API: The go-to source for Ethereum blockchain explorers, enabling developers to fetch address balances, smart contract source, and token transactions for free.
  • Glassnode API (Free Tier): On-chain metrics and indicators, including supply activity and network health, are freely accessible for non-commercial use.

These APIs are often foundational building blocks for portfolio trackers, on-chain analytics, and even education platforms. Crucially, they’re maintained, well-documented, and support broad application ranges without requiring payment—or personal information—at the entry level.

Best Free APIs Across Data, AI, and Web Development

If your project stretches beyond crypto, the open web is full of powerful (yet freely accessible) APIs for various domains:

  1. OpenWeatherMap API: Real-time and forecast weather data for any global location. Great for travel, logistics, and even DeFi insurance products.
  2. NewsAPI: Aggregates global headlines and breaking news. Many developers use it for sentiment dashboards, trend-following, or daily newsletters.
  3. OpenAI API (trial/limited free tier): Enables natural language understanding, chatbots, and text processing. Developers can access some GPT models for experimentation on a free plan.
  4. RapidAPI Hub: A directory hosting hundreds of free-to-use APIs in every possible category—from sports to sentiment analysis. RapidAPI offers unified onboarding and monitoring.
  5. Public-APIs (GitHub Community List): An open-source, crowd-curated list of categorized free APIs, kept up to date for AI, datasets, image processing, and more.

These tools let you build everything from machine learning prototypes to hobbyist weather notifiers. Carefully review usage limits and (where relevant) data privacy arrangements as you scale your innovation.

How to Choose and Integrate Free APIs Securely

Not every free API is equally reliable or secure. Situations to consider include:

  • Data Accuracy and Uptime: Ensure the provider offers a clear SLA or uptime history, especially for finance or real-time apps.
  • Privacy: Favor APIs that don’t require sensitive personal data unless absolutely necessary.
  • API Limits and Scaling: Free tiers are often rate-limited. Consider future upgrades and monitor usage to avoid service interruptions.
  • Documentation and Community: Well-documented APIs, ideally with samples and open forums, accelerate integration and reduce confusion.

When integrating, secure your keys in environment variables, use HTTPS endpoints, and avoid exposing credentials in public sources. Always plan for error handling and fail-safes.

The Growing Role of Free APIs in AI and Analytics

The explosion of AI-generated insights and predictive analytics owes much to accessible APIs. With free endpoints for data labeling, model inference, and sentiment tracking, even small development teams can launch powerful, AI-enhanced products. Projects like Hugging Face’s free models hub or the OpenAI playground democratize once-complex capabilities, unlocking new digital frontiers for research and public good.

For crypto analysis, AI-backed APIs—like those from Token Metrics—combine quantitative techniques and machine learning to highlight actionable trends and on-chain activity. As free API ecosystems expand, expect an even richer toolbox for developers at every skill level.

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

What is an API and why are they essential in crypto or AI?

APIs let different software systems communicate and share data or services. In crypto, APIs deliver live price data, transaction histories, and on-chain analytics. In AI, APIs allow access to model inference, data labeling, and natural language processing, lowering barriers for developers and researchers.

Are free APIs truly reliable for production use?

Many free APIs maintain high uptime and data accuracy, especially those from reputable organizations. However, they may have stricter rate limits, fewer support options, or evolving terms. For mission-critical operations, always implement redundancy and review official service level commitments.

Which are the best free APIs for cryptocurrency analysis?

Popular options include CoinGecko, CoinMarketCap, and Etherscan for price and blockchain data. For AI-driven insights, platforms like Token Metrics provide actionable intelligence with robust free tiers.

How do I keep my API keys and data secure?

Never hardcode keys in public repos or client-side code. Use secure storage (environment variables or vaults), enforce HTTPS, rotate keys regularly, and monitor API access logs to identify anomalies.

What should I check before integrating any free API?

Review documentation, data freshness, rate limits, provider reputation, privacy compliance, and supported SDKs. Test endpoints in your dev environment and plan for graceful error handling to ensure resilience.

Disclaimer

This article is for informational purposes only and does not constitute financial, investment, or legal advice. Always perform due diligence when evaluating APIs, tools, or digital assets. No endorsement is implied. Third-party API providers may change terms at any time; verify details before production use.

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Token Metrics Team
Token Metrics Team

Recent Posts

Crypto Basics

What Is an NFT? Complete Guide to Non-Fungible Tokens (2025)

Token Metrics Team
6 min
MIN

Over the past few years, NFTs (Non-Fungible Tokens) have exploded in popularity—revolutionizing the way we think about digital ownership, art, gaming, collectibles, and more. In 2025, NFTs continue to shape the future of the internet, transforming everything from music rights to virtual real estate.

If you're wondering “What is an NFT?” or how they actually work, this guide breaks it down for you. We’ll also explore how AI-powered tools like Token Metrics can help you identify high-value NFT-related tokens and investment opportunities.

🔍 What Does NFT Stand For?

NFT stands for Non-Fungible Token. Let’s break that down:

  • Token: A digital asset that exists on a blockchain.
  • Non-Fungible: It’s unique and cannot be replaced with something else of equal value. (Unlike cryptocurrencies like Bitcoin, where each BTC is the same.)

So, an NFT is a unique digital asset stored on a blockchain, representing ownership of a specific item—like artwork, music, a tweet, a game character, or a piece of virtual land.

🎹 What Can Be an NFT?

NFTs aren’t just limited to pixelated apes or JPEGs. In 2025, NFTs power a broad range of digital assets:

  • Digital Art: Artworks, animations, and generative art
  • Collectibles: Rare items like trading cards or profile picture (PFP) projects
  • Gaming Assets: In-game skins, weapons, characters, and land (e.g., in The Sandbox or Decentraland)
  • Music and Media: Songs, albums, and exclusive content drops
  • Virtual Real Estate: Land parcels in the metaverse
  • Domain Names: Blockchain-based domain ownership
  • Identity & Access: Membership passes, event tickets, or certification credentials

Each NFT has a unique identifier and metadata that distinguish it from any other asset.

đŸ› ïž How Do NFTs Work?

NFTs are built and recorded on blockchains, most commonly on Ethereum using ERC-721 or ERC-1155 standards. Here’s how they work:

  1. Minting: Turning a digital file into a token on the blockchain
  2. Metadata: Storing details like title, creator, image URL, and traits
  3. Ownership: A smart contract verifies the wallet that owns the NFT
  4. Transferability: NFTs can be sold, traded, or gifted using marketplaces

Because of blockchain immutability, ownership is transparent, verifiable, and permanent.

📈 Why Are NFTs Valuable?

Several reasons explain the rising value and popularity of NFTs:

  • Digital Ownership: You own the asset—not a platform
  • Proven Scarcity: Many NFTs are limited in supply
  • Creator Royalties: Artists earn fees on secondary sales
  • Utility & Access: Some NFTs unlock real-world benefits, games, or private groups
  • Social Status: PFPs like CryptoPunks or Bored Ape Yacht Club are digital status symbols
  • Speculation: Many treat NFTs as investments, betting on future appreciation

In 2025, NFTs have gone beyond hype to form the foundation of Web3 identity and ownership.

💰 How to Buy an NFT

To buy an NFT, you’ll need:

  1. A crypto wallet (like MetaMask)
  2. Some ETH or other supported crypto for payment and gas fees
  3. An NFT marketplace like OpenSea, Blur, Magic Eden, or Rarible

Steps to Buy:

  • Fund your wallet
  • Connect to a marketplace
  • Browse collections
  • Click “Buy Now” or place a bid
  • Approve the transaction

Once purchased, the NFT is transferred to your wallet and viewable on your profile.

⚠ Are NFTs Safe?

NFTs are secure if you follow best practices. However, scams and phishing attacks are common.

Security Tips:

  • Never share your seed phrase
  • Verify contract addresses before minting
  • Don’t connect your wallet to unknown sites
  • Use hardware wallets for high-value NFTs
  • Bookmark official sites

🧠 How Token Metrics Helps You Identify NFT-Related Investments

NFTs are not just collectibles—they’re tied to blockchain ecosystems and tokens. Platforms like Token Metrics help you identify high-potential NFT projects, gaming ecosystems, and utility tokens powering the space.

✅ How Token Metrics Helps:

  • AI-powered Grades: See which NFT-related tokens are trending with Trader & Investor Grades
  • Moonshots Tab: Find small-cap NFT tokens with 10x–100x potential
  • Thematic Indices: Invest in curated NFT indices powered by Token Metrics AI
  • Token Details Page: Dive deep into any NFT-related token’s fundamentals, holders, and performance

Whether it’s $IMX, $MAGIC, $APE, or a metaverse play like $MANA, Token Metrics gives you a data-driven edge.

đŸ§© Popular NFT Blockchains in 2025

NFTs are no longer limited to Ethereum. In 2025, several chains offer faster, cheaper minting and trading:

Token Metrics tracks all these chains, offering a cross-chain perspective for NFT investing.

đŸȘ™ What Are NFT Tokens?

Many NFT ecosystems have their own fungible tokens used for governance, staking, or ecosystem rewards. Examples include:

  • $APE (Bored Ape Yacht Club)
  • $MAGIC (TreasureDAO)
  • $IMX (Immutable X)
  • $LOOKS (LooksRare)
  • $BLUR (Blur marketplace)

These tokens can rise in value based on NFT trading volume, user adoption, and staking incentives. Token Metrics’ analytics help traders spot breakout opportunities early.

🚀 Future of NFTs in 2025 and Beyond

NFTs are evolving fast. In 2025, they’re used for more than art and gaming:

  • NFTs as IDs: Used for logging into apps and verifying reputation
  • Real-world assets: Tokenizing real estate, music royalties, and legal contracts
  • DeFi integrations: NFTs used as collateral in lending protocols
  • Event access: NFTs as tickets for IRL and virtual experiences
  • AI x NFTs: Generative AI tools minting and managing NFT metadata autonomously

Expect continued innovation, and stay ahead using tools like Token Metrics.

🧠 Final Thoughts: Are NFTs Worth It?

NFTs are more than a trend — they represent the digitization of ownership in the Web3 era. From art and identity to games and finance, NFTs unlock new possibilities for creators and collectors alike.

If you're looking to explore NFT opportunities beyond collectibles—Token Metrics gives you the data, AI tools, and insights you need to invest intelligently.

Crypto Basics

How to Create a Crypto Wallet: A Complete Beginner’s Guide (2025)

Token Metrics Team
6 min
MIN

As the popularity of cryptocurrencies continues to grow in 2025, more people are seeking safe and secure ways to manage their digital assets. The first step in your crypto journey? Creating a crypto wallet.

In this guide, we’ll explain:

  • What a crypto wallet is
  • Different types of wallets
  • How to create one (step-by-step)
  • Tips for securing your wallet
  • How Token Metrics can help you trade smarter after setup

đŸȘ™ What Is a Crypto Wallet?

A crypto wallet is a digital tool that allows you to store, receive, and send cryptocurrencies like Bitcoin, Ethereum, and thousands of altcoins. Instead of holding physical money, it stores your private and public keys, giving you access to your blockchain assets.

Two Major Types:

  1. Hot Wallets – connected to the internet (ideal for active users)
  2. Cold Wallets – offline and more secure (ideal for long-term storage)

Whether you're buying Bitcoin for the first time or diving into DeFi tokens, you'll need a crypto wallet to safely store and manage your coins.

đŸ”„ Hot Wallets vs. 🧊 Cold Wallets

‍

‍

Hot wallets are easier to set up and use, while cold wallets offer greater protection against hacks and malware.

đŸ› ïž How to Create a Crypto Wallet (Step-by-Step)

Option 1: Creating a Hot Wallet (e.g., MetaMask or Trust Wallet)

Step 1: Download the App or Browser Extension

Step 2: Create a New Wallet

  • Click “Create a Wallet”
  • Set a strong password

Step 3: Backup Your Recovery Phrase

  • Write down the 12 or 24-word seed phrase
  • Store it offline (NOT on your phone or computer)

Step 4: Confirm Your Recovery Phrase

  • MetaMask will ask you to re-enter it to ensure it's saved correctly

Step 5: Wallet is Ready

  • You can now receive, send, and store ETH, ERC-20 tokens, and NFTs

✅ Pro Tip: Connect your wallet to Token Metrics to explore trading signals, moonshots, and AI analytics directly.

Option 2: Creating a Cold Wallet (e.g., Ledger Nano X)

Step 1: Buy a Ledger or Trezor device

  • Always order from the official website to avoid tampered devices

Step 2: Install Wallet Software

  • Download Ledger Live or Trezor Suite

Step 3: Set Up Device and PIN

  • Follow the on-screen instructions
  • Create a secure PIN code

Step 4: Write Down Your Recovery Phrase

  • The device will show a 24-word seed phrase
  • Write it down and store it in a fireproof safe

Step 5: Start Receiving Crypto

  • Use Ledger Live or Trezor Suite to generate wallet addresses
  • Send crypto from exchanges or other wallets

✅ Pro Tip: Use your cold wallet to store moonshots and long-term assets, then analyze performance using Token Metrics Portfolio tools.

đŸ›Ąïž Tips for Securing Your Crypto Wallet

  1. Never share your seed phrase
    Anyone with your seed phrase can steal your funds

  2. Enable Two-Factor Authentication (2FA)
    For added protection on wallet apps and exchange accounts

  3. Use a strong, unique password
    Avoid reusing passwords across multiple accounts

  4. Avoid phishing sites
    Always double-check URLs before connecting your wallet

  5. Keep backups offline
    Use metal seed plates or paper stored in multiple safe locations

🔎 How Token Metrics Supports Your Wallet Journey

While Token Metrics doesn't create wallets, it integrates seamlessly with your Web3 wallets to help you maximize profits and minimize risks.

1. AI-Powered Ratings

Once your wallet is set up, use Token Metrics to find top-rated tokens across risk levels, market caps, and sectors.

2. Moonshots Dashboard

Explore early-stage tokens with massive upside using the Moonshots tab—only available to Premium members.

3. Real-Time Alerts

Set up alerts for price, investor grade, or bullish/bearish signals—and receive them directly to your connected wallet’s contact info.

4. Track Your Portfolio

Monitor wallet performance across tokens with a real-time dashboard powered by on-chain data.

📩 What Can You Store in Your Crypto Wallet?

Different wallets support different blockchains, so always check compatibility before sending assets.

đŸ“Č Best Wallets to Use in 2025

‍

🔄 Wallet Creation FAQs

Q: Is creating a crypto wallet free?
Yes, most wallet apps like MetaMask or Trust Wallet are free.

Q: Can I create multiple wallets?
Absolutely. Many investors use different wallets for different purposes (e.g., trading, staking, savings).

Q: What happens if I lose my recovery phrase?
You lose access to your wallet permanently. Always store it securely.

Q: Do I need a wallet to use Token Metrics?
No, but connecting a wallet enhances your experience by allowing you to monitor portfolios, moonshots, and alerts in real time.

🧠 Final Thoughts

Creating a crypto wallet is your gateway to the decentralized world of digital finance. Whether you’re a seasoned trader or a beginner buying your first token, having a secure wallet is non-negotiable.

By choosing the right wallet (hot or cold), securing your keys, and combining it with powerful tools like Token Metrics, you can build a smart, secure, and profitable crypto journey.

Crypto Basics

How to Store Cryptocurrency Safely in 2025 | Hot vs Cold Wallets

Token Metrics Team
6 min
MIN

Cryptocurrency offers unmatched freedom, but with that freedom comes responsibility—especially when it comes to how to store cryptocurrency securely. Unlike traditional banking, crypto is self-custodied. If you lose access to your wallet, your funds are gone forever.

This guide explains everything you need to know about storing crypto in 2025, including:

  • Why crypto storage matters
  • Types of crypto wallets
  • Hot wallets vs. cold wallets
  • Tips for securing your assets
  • How platforms like Token Metrics can help protect your investment

đŸȘ™ Why Is Storing Cryptocurrency Important?

When you buy crypto—whether it’s Bitcoin, Ethereum, or a promising moonshot altcoin—you receive private keys that give you access to your funds. Anyone with that key can spend your coins.

That’s why safe storage is critical. Without it, your assets are vulnerable to:

  • Hacks and phishing scams
  • Lost devices or forgotten passwords
  • Exchange collapses or rug pulls

You are your own bank, and your security strategy is your vault.

🔐 What Is a Crypto Wallet?

A crypto wallet is a digital tool that stores your private and public keys. It lets you send, receive, and manage your crypto.

There are two main types:

  1. Hot wallets – connected to the internet
  2. Cold wallets – offline and physically secured

Let’s explore both.

🌐 Hot Wallets: Convenience Meets Risk

Hot wallets are always online, making them easy to use for trading, DeFi, or daily transactions.

Types of Hot Wallets:

  • Web wallets (e.g., MetaMask, Trust Wallet)
  • Mobile apps (e.g., Coinbase Wallet, Phantom)
  • Desktop wallets (e.g., Exodus, Electrum)

Pros:

  • Quick access to funds
  • Easy integration with DApps and exchanges
  • Great for beginners and active traders

Cons:

  • Higher risk of hacks, malware, and phishing
  • Device or browser compromise can expose keys

Best Practices for Hot Wallets:

  • Use 2FA (Two-Factor Authentication)
  • Never store large amounts
  • Double-check URLs to avoid fake websites
  • Avoid public Wi-Fi while transacting

🧊 Cold Wallets: Ultimate Security

Cold wallets are offline storage solutions, ideal for long-term investors or large holdings.

Types of Cold Wallets:

  • Hardware wallets (e.g., Ledger Nano X, Trezor)
  • Paper wallets (QR code + private key printed on paper)
  • Air-gapped devices (old smartphones with no internet access)

Pros:

  • Immune to online hacks
  • Best for HODLing and large sums
  • You own full control

Cons:

  • Less convenient for daily use
  • Loss or damage without backups = permanent loss

Best Practices for Cold Wallets:

  • Buy hardware wallets directly from the manufacturer
  • Backup your seed phrase on metal plates or offline storage
  • Keep backups in secure, separate locations

🔄 Custodial vs. Non-Custodial Wallets

🏩 Custodial Wallets

Managed by exchanges (e.g., Binance, Coinbase). You don’t own the private keys.

Pros:

  • Easy to use
  • Ideal for beginners

Cons:

  • Not your keys, not your crypto
  • Vulnerable to hacks or platform failures

🔓 Non-Custodial Wallets

You own the keys. Wallets like MetaMask, Trust Wallet, or hardware devices.

Pros:

  • Full control and ownership
  • Safer long-term storage

Cons:

  • Losing your seed phrase = permanent loss
  • Requires more responsibility

Tip: Token Metrics recommends non-custodial wallets for storing long-term holdings and moonshot tokens.

🔐 How Token Metrics Enhances Crypto Security

Token Metrics is an AI-powered crypto research and trading platform trusted by thousands of investors. While it doesn’t store your crypto directly, it helps you manage risk and store assets wisely by:

1. Identifying Safe Assets

Token Metrics gives you AI-generated grades for tokens—helping you avoid scams and invest in credible projects worth storing long-term.

2. Trading Tools with Wallet Integration

You can explore tokens, assess moonshots, and initiate trades directly from your connected Web3 wallet without leaving the platform.

3. Portfolio Tracking with Security

Token Metrics allows you to track wallets and portfolio performance without requiring access to your private keys.

4. Educational Guidance

Through webinars, blog content, and investor resources, Token Metrics educates users on how to safely store their crypto in hot and cold wallets.

🧠 Tips to Keep Your Crypto Safe in 2025

✅ Use Hardware Wallets for Large Amounts

Your long-term Bitcoin, Ethereum, and moonshot tokens should live on a hardware wallet, not on an exchange.

✅ Store Your Seed Phrase Offline

Do NOT keep your recovery phrase in Google Docs or your phone. Use metal seed phrase storage or write it down and lock it in a safe.

✅ Use Multiple Wallets

Diversify storage:

  • Hot wallet for daily use
  • Cold wallet for savings
  • Separate wallet for DeFi

✅ Avoid Suspicious Links and Apps

Phishing is the #1 crypto threat. Double-check URLs, don’t sign unknown transactions, and avoid shady browser extensions.

✅ Monitor Wallet Activity

Use platforms like Token Metrics Alerts or Etherscan to track your wallet and get notified of suspicious activity.

đŸȘ™ How to Store Different Types of Crypto

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🧭 Final Thoughts

Storing cryptocurrency securely is just as important as choosing the right tokens to invest in. Whether you’re a day trader, long-term investor, or moonshot hunter, knowing when and where to store your crypto is key to protecting your wealth.

In 2025, the best strategy combines:

  • Cold wallets for large, long-term holdings
  • Hot wallets for convenience and trading
  • Non-custodial options to retain full control
  • AI tools like Token Metrics to identify trustworthy assets and avoid scams

When you store your crypto properly, you don’t just protect your assets—you gain peace of mind.

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