Research

Best Practices for Storing and Accessing API Keys in Your Applications

Learn industry-standard strategies for storing and accessing API keys securely in your apps. Explore tools, common mistakes to avoid, and how to mitigate risk in crypto or AI applications.
Token Metrics Team
6
MIN

API keys are a critical part of modern application development—enabling powerful third-party integrations while also presenting potential security risks. As APIs become the backbone of fintech, crypto, AI, and data applications, developers must ask: what are the safest and most scalable ways to store and access API keys? Let’s explore essential strategies, tools, and risks when handling sensitive API credentials.

Why API Key Security Matters

API keys function like digital passports, granting your application access to valuable services—from price feeds and SMS messaging to trading platforms and blockchain analytics. An exposed API key can lead to data leaks, unauthorized transactions, inflated bills, or even broader system compromise. High-profile data breaches, such as those resulting from public code repositories exposing secrets, underline the real-world impact of poor API key management.

Moreover, regulations and best practices in the crypto and AI industries demand robust security measures. Protecting API keys is not just about your own infrastructure—it’s about the trust your users and partners have in your platform.

Common API Key Storage Mistakes

Many security mishaps stem from common mistakes that are easy to avoid with the right protocols. These include:

  • Hardcoding API keys in source code – This exposes keys in version control (e.g., GitHub), making them potentially public.
  • Storing keys in client-side code – Any key shipped to the browser or mobile app can be extracted, leading to unauthorized API use.
  • Committing .env or config files with secrets – Failing to exclude sensitive files from repositories is a frequent culprit in breaches.
  • Sharing keys over unsecured channels – Email, chat, or shared docs aren’t secure environments for exchanging sensitive credentials.

Avoiding these pitfalls is a foundational step in API key security, but more sophisticated controls are often necessary as your application scales.

Proven Methods for Secure API Key Storage

To shield your API keys from breach and misuse, modern applications should utilize several technical best practices and tools:

  1. Environment Variables:
    • Environment variables keep secrets outside of your source code and can be managed per deployment (development, testing, production).
    • Most frameworks (Node.js, Python, Java, etc.) support loading variables from a .env file not checked into git.
  2. Secrets Management Platforms:
    • Enterprise-grade solutions like AWS Secrets Manager, HashiCorp Vault, Google Secret Manager, or Azure Key Vault offer encrypted secret storage, fine-grained access control, and audit logs.
    • Automate credential rotation and tightly restrict which services/components can access keys.
  3. Server-Side Storage Only:
    • Never expose sensitive API keys in client-side or public code. Keys should reside on a backend server that acts as a proxy or securely facilitates the necessary logic.
  4. Configuration Management:
    • Utilize configuration files for parameters but reference secrets via environment variables or secret manager APIs.

Additionally, always use least privilege principles: grant API keys only the permissions required for specific actions, and leverage IP allowlists or referrer checks where supported by the API provider.

Secure Methods for Accessing API Keys in Your Applications

How your application retrieves and uses API keys can be just as important as where they’re stored. Consider these approaches:

  • Runtime Injection: Use secure deployment workflows (like CI/CD platforms) to inject secrets as runtime environment variables, ensuring they’re not embedded in disk snapshots.
  • API Secrets Fetching: Advanced orchestration tools allow your app to fetch secrets at startup from a remote vault using temporary, tightly-scoped access tokens.
  • Encrypted Storage: If secrets must reside on disk (e.g., for legacy apps), encrypt both the file and filesystem, and restrict OS-level permissions.
  • Monitoring Access: Enable audit logging for each secret access, and set up alerts for anomalies like rapid key usage/rotation attempts.

Developers can further reduce risk by implementing rate limiting, automated key revocation/rotation, and zero trust policies—especially in large-scale or multi-developer environments.

Frameworks and Tools for API Key Management

Choosing the right tools can simplify and strengthen your API key security model. Some popular frameworks and services include:

  • dotenv (Node.js), python-dotenv: Read environment variables from files excluded from version control.
  • AWS Secrets Manager, Google Secret Manager, Azure Key Vault, HashiCorp Vault: Automated secrets storage, encryption, and access control, ideal for production-scale environments.
  • Kubernetes Secrets: Manage secrets in containerized environments with role-based access control and workload isolation.
  • CI/CD Secret Management: GitHub Actions, GitLab CI, and similar services let you define secret variables outside your repository for safe deployment workflows.

When connecting to crypto or AI services via API—such as Token Metrics—these tools make safe integration straightforward while maintaining regulatory compliance and auditability.

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FAQs on API Key Storage and Access

What happens if my API key is exposed?

If an API key is leaked, attackers could exploit your account to perform unauthorized transactions, scrape data, or exhaust your API limits. It’s essential to immediately revoke and regenerate compromised keys, audit usage, and identify the exposure vector.

Should I use the same API key in development and production?

No. Always generate separate API keys for each environment. This limits the impact of a potential leak and helps with auditing and troubleshooting.

Is it safe to store API keys in a database?

Only if the keys are encrypted at rest and the database access is strictly controlled. Prefer specialized secrets managers over general-purpose databases for handling sensitive keys.

How often should API keys be rotated?

Regular key rotation reduces risk from undetected exposures. The frequency depends on the sensitivity of the APIs in use—critical infrastructure often rotates every 90 days or less. Always rotate keys after a possible leak.

Can I share API keys with my team?

Share only through secure, auditable channels and never through unsecured messaging or docs. Use role-based permissions so each person has only the access they need, and revoke keys if team members leave.

Disclaimer

This content is provided for educational and informational purposes only. It does not constitute software security advice or an offer to buy or sell any financial product. Always perform your own due diligence and consult with appropriate professionals before implementing sensitive system changes.

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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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