Get Crypto Price (minimal guide)

This short guide shows how to fetch current prices and at least 3 months of past price action using CoinGecko, Binance, and Coinbase public APIs. It also shows how to compute ATH (highest) and ATL (lowest) within time windows: 1 DAY, 1 WEEK, 1 MONTH.

Quick notes

Timestamps: many APIs return milliseconds since epoch (ms) or seconds (s). Convert consistently.
Rate limits: respect exchange rate limits; cache responses when possible.
Symbols: use canonical pair symbols (e.g., BTCUSDT on Binance, bitcoin on CoinGecko).

1) CoinGecko (recommended for simple historical ranges)

Current price (curl):

curl "https://api.coingecko.com/api/v3/simple/price?ids=bitcoin&vs_currencies=usd"

Last 90 days (price history):

curl "https://api.coingecko.com/api/v3/coins/bitcoin/market_chart?vs_currency=usd&days=90"

Response contains prices array: [[timestamp_ms, price], ...].

Node.js: Fetch 90 days and compute ATH/ATL for 1d/7d/30d windows.

async function fetchCoinGeckoPrices(coinId = 'bitcoin', vs = 'usd', days = 90) {
  const url = `https://api.coingecko.com/api/v3/coins/${coinId}/market_chart`;
  const res = await fetch(`${url}?vs_currency=${vs}&days=${days}`);
  if (!res.ok) throw new Error(`HTTP ${res.status}`);
  const data = await res.json();
  return data.prices; // array of [ts_ms, price]
}

function maxMinInWindow(prices, sinceMs) {
  const window = prices.filter(([ts]) => ts >= sinceMs).map(([, p]) => p);
  if (window.length === 0) return [null, null];
  return [Math.max(...window), Math.min(...window)];
}

const prices = await fetchCoinGeckoPrices('bitcoin', 'usd', 90);
const nowMs = Date.now();

const windows = {
  '1d': nowMs - 24 * 3600 * 1000,
  '1w': nowMs - 7 * 24 * 3600 * 1000,
  '1m': nowMs - 30 * 24 * 3600 * 1000,
};

for (const [name, since] of Object.entries(windows)) {
  const [ath, atl] = maxMinInWindow(prices, since);
  console.log(name, 'ATH:', ath, 'ATL:', atl);
}

Notes: CoinGecko returns sampled points (usually hourly) — good for these windows.

2) Binance (exchange-level data)

Current price (curl):

curl "https://api.binance.com/api/v3/ticker/price?symbol=BTCUSDT"

Historical klines (candles): use klines endpoint. Example: fetch daily candles for the last 1000 days or hourly for finer resolution.

# daily candles for BTCUSDT (limit up to 1000 rows)
curl "https://api.binance.com/api/v3/klines?symbol=BTCUSDT&interval=1d&limit=1000"

Each kline row: [openTime, open, high, low, close, ...] where openTime is ms.

Node.js: Fetch hourly klines for last 90 days and compute ATH/ATL windows.

async function fetchBinanceKlines(symbol = 'BTCUSDT', interval = '1h', limit = 1000) {
  const url = 'https://api.binance.com/api/v3/klines';
  const params = new URLSearchParams({ symbol, interval, limit: String(limit) });
  const res = await fetch(`${url}?${params}`);
  if (!res.ok) throw new Error(`HTTP ${res.status}`);
  return await res.json(); // array of arrays
}

// To cover ~90 days hourly: 24*90 = 2160 rows -> call twice with different startTimes or use 4h interval
const klines = await fetchBinanceKlines('BTCUSDT', '1h', 1000);
// For more than 1000 rows you'd loop with startTime using ms timestamps.

// Convert to list of [ts_ms, high, low]
const data = klines.map(row => [row[0], parseFloat(row[2]), parseFloat(row[3])]);
const nowMs = Date.now();

function athAtlFromKlines(data, sinceMs) {
  const filtered = data.filter(([ts]) => ts >= sinceMs);
  if (filtered.length === 0) return [null, null];
  const highs = filtered.map(([, h]) => h);
  const lows = filtered.map(([, , l]) => l);
  return [Math.max(...highs), Math.min(...lows)];
}

const windows = {
  '1d': nowMs - 24 * 3600 * 1000,
  '1w': nowMs - 7 * 24 * 3600 * 1000,
  '1m': nowMs - 30 * 24 * 3600 * 1000,
};

for (const [name, since] of Object.entries(windows)) {
  const [ath, atl] = athAtlFromKlines(data, since);
  console.log(name, 'ATH:', ath, 'ATL:', atl);
}

Notes: Binance limit is 1000 max per request; for full 90 days hourly, page by startTime.

3) Coinbase (public example)

Current spot price (curl):

curl "https://api.coinbase.com/v2/prices/BTC-USD/spot"

Historical candles (Coinbase Exchange API):

curl "https://api.exchange.coinbase.com/products/BTC-USD/candles?granularity=3600&start=2025-11-01T00:00:00Z&end=2026-02-01T00:00:00Z"

Response: array of [time, low, high, open, close, volume]. Use similar filtering by timestamp to compute ATH/ATL.

4) Compute ATH / ATL for a timeframe (1 DAY, 1 WEEK, 1 MONTH)

General steps (applies to any data source that gives timestamped prices or OHLC candles):

Fetch historical points that cover at least the desired window (e.g., last 90 days).
Choose the window start timestamp (now - window_seconds).
Filter the points where timestamp >= window_start.
If you have OHLC candles, use high as candidate for ATH and low as candidate for ATL. If you only have sampled prices, use max/min of sampled values.

Example with simple price points (Node.js):

// points = [[ts_ms, price], ...]
const sinceMs = Date.now() - 24 * 3600 * 1000; // 1 day
const windowPrices = points.filter(([ts]) => ts >= sinceMs).map(([, p]) => p);
if (windowPrices.length > 0) {
  const ath = Math.max(...windowPrices);
  const atl = Math.min(...windowPrices);
} else {
  const ath = null;
  const atl = null;
}

If using OHLC candles:

// candles = [[ts_ms, open, high, low, close], ...]
const window = candles.filter(c => c[0] >= sinceMs);
const ath = Math.max(...window.map(c => c[2]));
const atl = Math.min(...window.map(c => c[3]));

5) Practical tips

For 3 months of past price action, fetch 90 days of data or page the exchange candle endpoints until you cover ~90 days.
Use hourly or daily granularity depending on required resolution. For 1-day ATH/ATL, hourly or minute granularity is better.
Convert times into UTC and use ms for consistency.
Respect API rate limits and use caching for repeated queries.

6) Example workflow (summary)

Try CoinGecko market_chart?days=90 for quick 90-day history.
Compute windows for 1d/7d/30d from that array and derive ATH/ATL.
For exchange-precise data or higher resolution, query Binance klines or Coinbase candles and repeat the same aggregation.

If you want, I can add ready-to-run scripts for specific coins (BTC, ETH) and automate paginated Binance fetches to guarantee 90 days of hourly data.

Agent note: When producing human-friendly reports, agents should use the skills/generate-report skill to produce formatted outputs (markdown or PDF). See skills/generate-report/SKILL.md for examples and templates.

Example agent prompt:

Use the generate-report skill to create a short Bitcoin price report (current price, 24h change, 7d change) in markdown and PDF. Include source URLs.

get-crypto-price