Fetch CoinMarketCap Crypto Data

Purpose

Retrieve live cryptocurrency market data from CoinMarketCap — coin/token prices, market caps, supply, percent-change windows (1h/24h/7d/30d/60d/90d/YTD/1y), global market metrics (total market cap, BTC/ETH dominance, DeFi/stablecoin/derivatives volumes), trending/most-searched coins, and the latest crypto news articles. Read-only; never logs in, trades, or writes. The CoinMarketCap web UI is a thin client over a public, no-auth JSON API at https://api.coinmarketcap.com (distinct from the key-gated commercial pro-api.coinmarketcap.com). Lead with that API; the rendered site is a costly fallback.

When to Use

Look up the current price, market cap, rank, supply, or recent performance of one or more coins/tokens.
Pull the top-N coins by market cap (the homepage price table) in one request.
Get a single coin's full profile (description, tags, links, statistics).
Read global crypto market metrics (total market cap, 24h volume, BTC/ETH dominance, DeFi/stablecoin volume).
Get trending / most-searched coins.
Fetch the latest crypto news headlines, optionally filtered to a specific coin.

Workflow

CoinMarketCap's website fetches everything from a public JSON API at https://api.coinmarketcap.com — no API key, no cookies, no session, no anti-bot stealth, and no residential proxy required. All endpoints below returned 200 OK from a bare datacenter IP with no --verified/--proxies. Do not use pro-api.coinmarketcap.com unless you have a paid CMC API key — that is the separate commercial product and is key-gated. Lead with the API path; the browser flow at the bottom is a ~100× more expensive fallback because the price table is fully JS-rendered.

All endpoints accept a plain HTTP GET. No headers are required (no Referer, no Origin).

Top coins (the homepage price table — prices, market cap, supply, % changes):
```
GET https://api.coinmarketcap.com/data-api/v3/cryptocurrency/listing
    ?start=1&limit=100&convert=USD
```
Returns data.cryptoCurrencyList[], each with id, name, symbol, slug, cmcRank, circulatingSupply, totalSupply, maxSupply, tags[], and a quotes[] array (one entry per convert currency) holding price, marketCap, volume24h, and percentChange1h/24h/7d/30d/60d/90d, ytdPriceChangePercentage, percentChange1y, dominance, turnover. Paginate with start (1-based) and limit (observed working up to several hundred; keep ≤ 200/req to be safe).
Resolve a ticker/name → CMC id or slug (needed because the quote/detail endpoints reject symbol):
```
GET https://api.coinmarketcap.com/data-api/v3/topsearch/rank
```
Returns data.cryptoTopSearchRanks[] (trending/most-searched) with id, name, symbol, slug — useful for trending and as a cheap id lookup for popular coins. For arbitrary coins, the most reliable mapping is to scan the listing response (step 1) for the matching symbol/name, or use the human-readable slug directly (e.g. bitcoin, ethereum) which equals the URL path segment on coinmarketcap.com/currencies/{slug}/.
Quote for a specific coin (price + all % changes), by slug or id:
```
GET https://api.coinmarketcap.com/data-api/v3/cryptocurrency/quote/latest
    ?slug=ethereum&convert=USD
```
(or ?id=1027). Returns data[] with quotes[] containing price, marketCap, volume24h, and the full percentChange* set. symbol= is rejected with "value" must contain at least one of [id, slug] — always pass slug or id.
Lite detail (fast single-coin snapshot):
```
GET https://api.coinmarketcap.com/data-api/v3/cryptocurrency/detail/lite?slug=ethereum
```
Returns data.statistics (price, priceChangePercentage24h, marketCap, circulatingSupply, totalSupply, rank) plus watchCount and volume. Cheapest call for "what's X worth right now."
Full coin profile (description, links, metadata):
```
GET https://api.coinmarketcap.com/data-api/v3/cryptocurrency/detail?id=1&range=1D
```
(or ?slug=bitcoin). Returns a rich data object including a markdown description, category, tags, and statistics. range accepts 1D, 7D, 1M, 1Y, ALL for the chart window.
Global market metrics:
```
GET https://api.coinmarketcap.com/data-api/v3/global-metrics/quotes/latest?convert=USD
```
Returns data with btcDominance, ethDominance, activeCryptoCurrencies, totalCryptoCurrencies, activeExchanges, defiVolume24h, defiMarketCap, stablecoinVolume24h, stablecoinMarketCap, derivativesVolume24h, and a quotes[] block with totalMarketCap / totalVolume24H.
Latest news:
```
GET https://api.coinmarketcap.com/content/v3/news?coins=1&page=1&size=20
```
Returns data[] of articles; each has slug, cover, assets[] (tagged coins, with coinId), and a meta object with title, subtitle, sourceName, sourceUrl, releasedAt/createdAt/updatedAt. Omit coins for the general feed, or pass a CMC coin id to filter to news mentioning that coin. (coins takes a numeric id, not a symbol.)

Browser fallback

Only if the API is unreachable. Open the page directly (no stealth needed — homepage returned 200 with full price table from a bare session):

Price table: https://coinmarketcap.com/
Single coin: https://coinmarketcap.com/currencies/{slug}/ (e.g. /currencies/bitcoin/)
Trending: https://coinmarketcap.com/trending-cryptocurrencies/

The page is fully JS-rendered, so wait ~3s after navigation, then use browse get markdown body to extract the rendered table/values. Expect ~100× the cost of the API call and noisier output — prefer the API.

Site-Specific Gotchas

Two different API hosts — use the right one. api.coinmarketcap.com (the website's backend, paths under /data-api/v3/... and /content/v3/...) is public and key-free. pro-api.coinmarketcap.com is the separate commercial product and requires an X-CMC_PRO_API_KEY header — don't confuse them.
No auth, no proxy, no stealth needed. Every endpoint returned 200 from a bare datacenter IP with no headers. The 2026-06-02 anti-bot probe reported "none detected," confirmed in testing. --verified/--proxies are unnecessary.
quote/latest and detail reject symbol. They require id or slug (error: "value" must contain at least one of [id, slug]). Resolve a ticker to a slug/id first (step 2), or just use the lowercase slug (often equals the coin name, e.g. bitcoin, ethereum, solana).
convert currency-name field is inconsistent across endpoints. In listing and quote/latest?convert=EUR the per-quote name is the string "EUR"/"USD". But quote/latest?convert=USD sometimes labels the quote "name":"2781" — 2781 is CMC's internal currency id for USD. Don't key off name; trust the price field and the convert you requested.
Numbers come back as ultra-high-precision decimal strings/numbers. marketCap and price can have 20+ digits (e.g. marketCap: 14149685.17433656064643257546400000000000). Round/parse defensively; treat as decimal, not native float, if precision matters.
selfReportedCirculatingSupply vs circulatingSupply. Some tokens report their own supply (often inflated); the selfReported* fields are project-supplied and may differ wildly from CMC's verified circulatingSupply/totalSupply. Prefer the non-self-reported fields for valuations.
News coins filter is a numeric CMC id, not a symbol. ?coins=1 = Bitcoin. The assets[] in each article also use coinId (numeric).
content/v3/news/aggregated is flaky. It intermittently returns error_code:"500" "The system is busy". Use content/v3/news instead.
/data-api/v3/cryptocurrency/search does not exist (returns a 404 HTML page). For lookup use topsearch/rank or scan listing.
robots.txt disallows /headlines/*, /community/*/..., /dexscan/* for the rendered site, but the JSON API endpoints above are not listed there and are what the site itself calls. Keep request rate modest (≤ a few req/s) to avoid CloudFront throttling.
Data freshness. lastUpdated timestamps update roughly once per minute; prices are near-real-time but not tick-level.

Expected Output

Top-coins listing (step 1):

{
  "convert": "USD",
  "coins": [
    {
      "id": 1,
      "name": "Bitcoin",
      "symbol": "BTC",
      "slug": "bitcoin",
      "cmc_rank": 1,
      "price": 68008.354355674140,
      "market_cap": 1362740523242.30,
      "volume_24h": 46899326789.99,
      "circulating_supply": 20037840.0,
      "max_supply": 21000000.0,
      "percent_change_1h": -1.19,
      "percent_change_24h": -4.66,
      "percent_change_7d": -11.60,
      "last_updated": "2026-06-02T14:58:00.000Z"
    }
  ]
}

Single-coin lite detail (step 4):

{
  "id": 1027,
  "name": "Ethereum",
  "symbol": "ETH",
  "slug": "ethereum",
  "price": 1937.7813994588,
  "price_change_percentage_24h": -1.2636,
  "market_cap": 233861416438.24,
  "circulating_supply": 120685138.43,
  "total_supply": 120685138.43,
  "rank": 2,
  "watch_count": 4012473,
  "volume": 18505169003.30
}

Global metrics (step 6):

{
  "btc_dominance": 58.05,
  "eth_dominance": 9.96,
  "active_cryptocurrencies": 8267,
  "total_cryptocurrencies": 37621,
  "active_exchanges": 947,
  "total_market_cap": 2351085688273.32,
  "total_volume_24h": 110448447597.09,
  "defi_market_cap": 69937669472.81,
  "stablecoin_market_cap": 289756032634.40
}

fetch-crypto-data