Research

API Keys Explained: Secure Access for Developers

Learn what an api key is, how it works, and practical security and management techniques for developers and crypto integrations. Actionable best practices for safe key handling.
Token Metrics Team
5
MIN

Every modern integration — from a simple weather widget to a crypto analytics agent — relies on API credentials to authenticate requests. An api key is one of the simplest and most widely used credentials, but simplicity invites misuse. This article explains what an api key is, how it functions, practical security patterns, and how developers can manage keys safely in production.

What an API Key Is and How It Works

An api key is a short token issued by a service to identify and authenticate an application or user making an HTTP request. Unlike full user credentials, api keys are typically static strings passed as headers, query parameters, or request bodies. On the server side, the receiving API validates the key against its database, checks permissions and rate limits, and then either serves the request or rejects it.

Technically, api keys are a form of bearer token: possession of the key is sufficient to access associated resources. Because they do not necessarily carry user-level context or scopes by default, many providers layer additional access-control mechanisms (scopes, IP allowlists, or linked user tokens) to reduce risk.

Common API Key Use Cases and Limitations

API keys are popular because they are easy to generate and integrate: you create a key in a dashboard and paste it into your application. Typical use cases include server-to-server integrations, analytics pulls, and third-party widgets. In crypto and AI applications, keys often control access to market data, trading endpoints, or model inference APIs.

Limitations: api keys alone lack strong cryptographic proof of origin (compared with signed requests), are vulnerable if embedded in client-side code, and can be compromised if not rotated. For higher-security scenarios, consider combining keys with stronger authentication approaches like OAuth 2.0, mutual TLS, or request signing.

Practical Security Best Practices for API Keys

Secure handling of api keys reduces the chance of leak and abuse. Key best practices include:

  • Least privilege: Create keys with the minimum permissions required. Use separate keys for read-only and write actions.
  • Rotate regularly: Implement scheduled rotation and automated replacement to limit exposure from undetected leaks.
  • Use environment variables and secrets managers: Never commit keys to source control. Use environment variables, vaults, or cloud KMS services to store secrets.
  • Restrict usage: Apply IP allowlists, referrer checks, or VPC restrictions where supported to limit where the key can be used.
  • Audit and monitor: Log usage, set alerts for anomalous patterns, and review dashboards for spikes or unexpected endpoints.
  • Expire and revoke: Use short-lived keys where possible; immediately revoke compromised keys and revoke unused ones.

These patterns are practical to implement: for example, many platforms offer scoped keys and rotation APIs so you can automate revocation and issuance without manual intervention.

Managing API Keys in Crypto and AI Workflows

Crypto data feeds, trading APIs, and model inference endpoints commonly require api keys. In these contexts, the attack surface often includes automated agents, cloud functions, and browser-based dashboards. Treat any key embedded in an agent as potentially discoverable and design controls accordingly.

Operational tips for crypto and AI projects:

  • Use separate keys per service and environment (dev, staging, production).
  • Scale permission granularity: allow market-data reads without trading execution permissions.
  • Encrypt keys at rest and limit human access to production secrets.
  • Integrate rate-limit and quota checks to avoid service disruption and to detect misuse quickly.

Platforms such as Token Metrics provide APIs tailored to crypto research and can be configured with scoped keys for safe consumption in analytics pipelines and AI agents.

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: What Is an API Key?

An api key is a token that applications send with requests to identify and authenticate themselves to a service. It is often used for simple authentication, usage tracking, and applying access controls such as rate limits.

FAQ: How should I store api keys?

Store api keys outside of code: use environment variables, container secrets, or a managed secrets store. Ensure access to those stores is role-restricted and audited. Never commit keys to public repositories or client-side bundles.

FAQ: What's the difference between an api key and an OAuth token?

API keys are static identifiers primarily for application-level authentication. OAuth tokens represent delegated user authorization and often include scopes and expiration. OAuth is generally more suitable for user-centric access control, while api keys are common for machine-to-machine interactions.

FAQ: How often should I rotate api keys?

Rotation frequency depends on risk tolerance and exposure: a common pattern is scheduled rotation every 30–90 days, with immediate rotation upon suspected compromise. Automate the rotation process to avoid service interruptions.

FAQ: What are signs an api key is compromised?

Watch for abnormal usage patterns: sudden spikes in requests, calls from unexpected IPs or geographic regions, attempts to access endpoints outside expected scopes, or errors tied to rate-limit triggers. Configure alerts for such anomalies.

FAQ: Can I restrict an api key to a single IP or domain?

Many providers allow IP allowlisting or referrer restrictions. This reduces the attack surface by ensuring keys only work from known servers or client domains. Use this in combination with short lifetimes and least-privilege scopes.

FAQ: How do api keys fit into automated AI agents?

AI agents that call external services should use securely stored keys injected at runtime. Limit their permissions to only what the agent requires, rotate keys regularly, and monitor agent activity to detect unexpected behavior.

Disclaimer

This article is educational and informational in nature. It is not investment, legal, or security advice. Evaluate any security approach against your project requirements and consult qualified professionals for sensitive implementations.

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Token Metrics Team
Token Metrics Team

Recent Posts

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

‍

🧭 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.

Token Metrics API

How to Build Crypto Trading Dashboard Using the Token Metrics Crypto Data API on Dune

Token Metrics Team
8 min
MIN

In today’s fast-paced crypto world, real-time data isn’t a luxury—it’s a necessity. For traders, analysts, and developers, being able to access live, actionable insights can mean the difference between profit and loss. That’s why the integration of the Token Metrics Crypto Data API with Dune is a game-changer for anyone seeking to create live dashboards backed by intelligent trading data.

In this post, we’ll walk through how to use this top crypto API to build dynamic dashboards on Dune. Whether you’re tracking bullish signals, backtesting trading strategies, or identifying top-performing tokens, this integration makes it possible—without any paid license.

Let’s dive into how you can use the best free crypto API available today to transform your trading.

What Is the Token Metrics Crypto Data API?

The Token Metrics Crypto Data API is a developer-focused gateway to powerful, AI-driven crypto data. It’s one of the top crypto APIs in 2025, giving you access to:

  • Real-time and historical trading signals
  • Proprietary trader and investor grades
  • Alpha metrics comparing trading vs. holding performance
  • Bullish and bearish token flags

This API is used by both professional quant traders and beginners seeking to automate insights. And the best part? Token Metrics provides free crypto API access to selected datasets, allowing you to create powerful dashboards without spending a dime.

Why Dune + Token Metrics API = Power Tools for Traders

Dune is a blockchain analytics platform that allows you to write SQL queries and create dashboards using on-chain and off-chain data. Now that Token Metrics datasets are available on Dune, you can combine the best of both worlds:

  • Free access to high-signal proprietary metrics
  • Real-time data visualizations via Dune’s drag-and-drop dashboard builder
  • Actionable insights based on AI-driven trading intelligence

This integration unlocks a whole new level of transparency and utility for crypto analysts, portfolio managers, and DeFi enthusiasts.

Getting Started: Accessing Token Metrics Data on Dune

To begin, create a free Dune account. Once logged in, navigate to the Token Metrics datasets. These are publicly accessible and updated regularly. You’ll find tables for:

  • trading_signals
  • trader_grades
  • investors_grades
  • tokens

Start a new SQL query and choose the dataset you want to explore. Here’s what you’ll find in the trading signals table:

‍

‍

Step-by-Step: Creating an Actionable Dashboard with Token Metrics Data

1. Query the Trading Signal Returns

Write a SQL query to calculate the average return of trading vs. holding strategies. For example:

This gives you the alpha—how much better the Token Metrics strategy performs compared to just HODLing.

In one real example, the average signal return across all tokens was 1630%, while holding returned just 400%. That’s a 12X improvement powered by this top crypto API.

2. Identify Top-Performing Tokens

Now let’s list tokens with the highest average alpha:

Tokens like BTC, ETH, BNB, and even newer ones like Virtuals stand out due to exceptional alpha performance.

3. Visualize Trader Grades vs. Alpha

The trader grade is a proprietary score from Token Metrics that predicts how favorable a token is for short-term traders.

Use a scatter plot to correlate trader grades with average alpha:

  • X-axis: Trader Grade
  • Y-axis: Average Alpha
  • Group by: Token Symbol

This helps you visually determine which tokens score high and offer exceptional returns—an essential tool for making actionable trading decisions.

4. Track the Latest Bullish Signals

Want to know which tokens are bullish right now? Here’s a query to find the most recent tokens flagged as bullish:

For example, on July 4th, tokens like BNB, XRP, and BTC were among the most recent bullish signals—perfect for immediate trade setups.

5. Build and Share Your Dashboard

Once you’ve run your queries:

  • Click “Add Visualization” in Dune
  • Choose from chart types (bar, scatter, progress bar, etc.)
  • Customize colors and filters
  • Combine multiple charts into a single dashboard

Your final product will be a real-time dashboard powered by the best crypto API, delivering insights that you—and your team—can act on instantly.

Why Token Metrics Is the Best Free Crypto API for Traders

Here’s why Token Metrics stands out among other APIs:

✅ AI-Driven Signals

Most APIs deliver raw data. Token Metrics provides curated signals, generated from machine learning models trained on market cycles, indicators, and price action.

✅ Proprietary Metrics

Access unique indicators like trader grade and investor grade, unavailable anywhere else.

✅ Real Historical Alpha

Use the API to backtest strategies. In the example shown, the AI strategy outperformed the market by over 1000X for some tokens.

✅ Seamless Integration

Whether you're using Dune, Zapier, OpenAI, or Eliza OS, Token Metrics is easy to integrate and query—making it the top crypto API for developers and analysts alike.

Final Thoughts

The combination of Token Metrics’ intelligent data and Dune’s visualization tools puts immense power in your hands. Whether you’re tracking market trends, building bots, or guiding portfolio decisions, this integration gives you everything you need to trade smarter.

With free access to real-time trading signals, alpha comparisons, and powerful visualizations, Token Metrics proves why it's the best crypto API for today’s data-driven investor.

Ready to try it out?
👉 Explore the Free Crypto API
👉 Start Building on Dune

Crypto Basics

What Is an ETF Stock? A Beginner’s Guide to Exchange-Traded Funds in 2025

Token Metrics Team
8 min
MIN

In today’s fast-moving financial markets, Exchange-Traded Funds, or ETF stocks, have emerged as one of the most popular investment vehicles for beginners and professionals alike. But what exactly is an ETF stock, how does it work, and why is it considered a smart way to invest?

This guide will walk you through everything you need to know about ETF stocks in 2025—including how they work, their benefits and risks, and how AI platforms like Token Metrics are changing the way people research and trade ETFs in both traditional and crypto markets.

📌 What Is an ETF Stock?

An ETF stock refers to a share of an Exchange-Traded Fund—a type of investment fund that trades on stock exchanges, much like individual company stocks. Each ETF holds a basket of underlying assets such as:

  • Stocks (e.g., S&P 500 companies)
  • Bonds
  • Commodities (like gold or oil)
  • Currencies
  • Cryptocurrencies (Bitcoin, Ethereum, etc.)

When you buy an ETF stock, you’re buying a fractional share of the entire portfolio of assets held by that ETF.

🔍 How Does an ETF Stock Work?

ETF stocks work like this:

  1. Creation: An asset management company (like BlackRock, Vanguard, or Fidelity) creates an ETF that tracks a specific index, sector, or asset type.
  2. Listing: The ETF is listed on a stock exchange such as the NYSE or Nasdaq.
  3. Trading: Investors can buy and sell ETF shares throughout the trading day, just like they would a stock like Apple or Tesla.
  4. Price Movement: The price of an ETF stock fluctuates during the day based on the Net Asset Value (NAV) of its holdings and supply-demand dynamics in the market.

This model provides a liquid, transparent, and low-cost way for investors to gain diversified exposure to entire markets or sectors.

📊 Example of an ETF Stock

A good example is the SPDR S&P 500 ETF Trust (SPY), which tracks the performance of the S&P 500 index. When you buy a share of SPY, you gain exposure to 500 of the largest U.S. companies—without needing to buy each stock individually.

✅ Benefits of ETF Stocks

ETF stocks offer numerous advantages for investors in 2025:

1. Diversification

Instead of buying individual assets, ETF stocks offer instant diversification by holding dozens or hundreds of securities in a single share.

2. Liquidity

ETFs are traded on exchanges, making them highly liquid. You can buy or sell them at market prices during normal trading hours.

3. Lower Costs

ETFs typically have low expense ratios (as low as 0.03%), especially compared to mutual funds or actively managed portfolios.

4. Transparency

Most ETFs disclose their holdings daily, giving investors a clear view into what they’re buying.

5. Flexibility

You can use ETFs for long-term investing, short-term trading, hedging, or generating income through dividends.

⚠ Risks of ETF Stocks

Despite their many benefits, ETF stocks do come with some risks:

1. Market Risk

ETF stocks are still subject to market volatility. If the underlying assets decline in value, so will the ETF.

2. Tracking Error

Some ETFs may not perfectly replicate the performance of their index due to fees, slippage, or illiquid assets.

3. Overexposure

Because ETFs make it easy to invest, some investors may unknowingly become overexposed to a particular sector or strategy.

4. Liquidity Risk

Not all ETFs are created equal. Low-volume ETFs may have wider bid-ask spreads, increasing trading costs.

đŸȘ™ Crypto ETFs: The New Frontier

In 2025, crypto ETF stocks have become a hot trend. These funds allow investors to gain exposure to digital assets without managing private keys, wallets, or blockchain protocols.

Types of crypto ETFs include:

  • Spot ETFs: Hold actual crypto assets (e.g., Bitcoin, Ethereum).
  • Futures ETFs: Track the price of crypto futures contracts.

Popular examples in 2025 include:

  • IBIT (BlackRock Bitcoin ETF)
  • FBTC (Fidelity Bitcoin ETF)
  • ETHX (Ethereum Spot ETF)

Crypto ETFs have opened the door for institutional and traditional investors to gain exposure to the crypto market in a regulated and simplified manner.

đŸ€– How Token Metrics Helps You Trade ETF Stocks Smarter

Whether you're interested in traditional ETF stocks or crypto ETFs, Token Metrics provides the AI-powered insights you need to make better investment decisions.

🔎 1. AI-Powered Ratings

Token Metrics assigns each token or ETF a Trader Grade and Investor Grade based on price trends, volume, volatility, and technical strength—making it easy to spot outperformers.

📈 2. Bullish and Bearish Signals

AI-driven signals show when it’s time to buy or sell based on real-time metrics like ETF inflows, exchange balances, and market sentiment.

📊 3. Price Forecasts

Get access to predictive models that estimate where Bitcoin, Ethereum, and major crypto ETFs are headed—based on 80+ factors.

🔔 4. Smart Alerts

Set custom alerts for ETF stock signals, price movements, or grade changes so you never miss an opportunity.

By combining ETF investing with Token Metrics’ AI analytics, you gain an informational edge in markets that move faster than ever.

📈 Popular ETF Stocks in 2025

Here’s a list of top-performing ETF stocks across traditional and crypto sectors:

🧠 Final Thoughts

ETF stocks are a powerful investment tool in 2025, offering instant diversification, low fees, and easy access to traditional and crypto markets. Whether you're looking to build a retirement portfolio or ride the next Bitcoin rally, ETF stocks make it easier than ever to invest with confidence.

And with platforms like Token Metrics, you don’t need to guess your way through ETF trading. Use AI-driven insights, price predictions, and real-time data to get ahead of the curve—no matter what markets you trade.

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