Best Free Finance APIs in 2026

const symbol = "AAPL";
const res = await fetch(
  `https://www.alphavantage.co/query?function=GLOBAL_QUOTE&symbol=${symbol}&apikey=YOUR_KEY`
);
const data = await res.json();
const q = data["Global Quote"];
console.log(`${symbol}: $${q["05. price"]}`);
console.log(`Change: ${q["10. change percent"]}`);

// No API key needed!
const res = await fetch(
  "https://api.coingecko.com/api/v3/simple/price?ids=bitcoin,ethereum,solana&vs_currencies=usd&include_24hr_change=true"
);
const data = await res.json();
Object.entries(data).forEach(([coin, info]) => {
  console.log(`${coin}: $${info.usd} (${info.usd_24h_change.toFixed(2)}%)`);
});

const res = await fetch(
  "https://api.polygon.io/v2/aggs/ticker/AAPL/prev?apiKey=YOUR_KEY"
);
const data = await res.json();
const r = data.results[0];
console.log(`AAPL: Open $${r.o}, Close $${r.c}`);
console.log(`Volume: ${r.v.toLocaleString()}`);

// Unofficial endpoint — use yfinance for Python instead
const res = await fetch(
  "https://query1.finance.yahoo.com/v8/finance/chart/MSFT?interval=1d&range=5d"
);
const data = await res.json();
const closes = data.chart.result[0].indicators.quote[0].close;
console.log("MSFT last 5 closes:", closes.map(c => "$" + c?.toFixed(2)));

const res = await fetch(
  "http://data.fixer.io/api/latest?access_key=YOUR_KEY&symbols=USD,GBP,JPY,CAD"
);
const data = await res.json();
console.log("Base: EUR");
Object.entries(data.rates).forEach(([currency, rate]) => {
  console.log(`  EUR/${currency}: ${rate}`);
});

// Test mode — no real charges
const res = await fetch("https://api.stripe.com/v1/payment_intents", {
  method: "POST",
  headers: {
    "Authorization": "Bearer sk_test_YOUR_KEY",
    "Content-Type": "application/x-www-form-urlencoded"
  },
  body: "amount=2000¤cy=usd&payment_method_types[]=card"
});
const intent = await res.json();
console.log(`Payment: ${intent.id} — ${intent.status}`);

const res = await fetch(
  "https://v6.exchangerate-api.com/v6/YOUR_KEY/latest/USD"
);
const data = await res.json();
console.log(`1 USD = ${data.conversion_rates.EUR} EUR`);
console.log(`1 USD = ${data.conversion_rates.GBP} GBP`);
console.log(`1 USD = ${data.conversion_rates.JPY} JPY`);