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coinmarketcap

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coinmarketcap
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scraping.md

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  • https://coinmarketcap.com — crypto market data. Three access paths tested: internal JSON API (fastest, no auth required), NEXTDATA from HTML pages, and browser DOM. All real-money price data confirmed accurate against...
  • Never use the browser for read-only CMC tasks. The internal API at api.coinmarketcap.com is accessible with no API key, no special headers, no auth — plain httpget works.
  • Do NOT use pro-api.coinmarketcap.com — that is the paid API requiring a key.
  • ---
Show full markdown

https://coinmarketcap.com — crypto market data. Three access paths tested: internal JSON API (fastest, no auth required), __NEXT_DATA__ from HTML pages, and browser DOM. All real-money price data confirmed accurate against displayed UI values.

Do this first: pick your access path

GoalBest approachLatency
Top N coins by market capInternal listing API~200ms
Single coin price/stats/ATHInternal detail API~100ms
Global market metricsInternal global-metrics API~65ms
All coins on homepage (101 items)__NEXT_DATA__ main page~700ms
Coin detail + full stats__NEXT_DATA__ currency page~700ms
Historical OHLCVInternal historical API~160ms
Exchange pairs for a coinInternal market-pairs API~200ms
News/articlesInternal content API~220ms

Never use the browser for read-only CMC tasks. The internal API at api.coinmarketcap.com is accessible with no API key, no special headers, no auth — plain http_get works.

Do NOT use pro-api.coinmarketcap.com — that is the paid API requiring a key.

Path 1: Internal listing API (fastest for ranked coins)

Returns CMC-ranked coins with full price data in one call. No auth needed.

python
import json

resp = json.loads(http_get(
    "https://api.coinmarketcap.com/data-api/v3/cryptocurrency/listing"
    "?start=1&limit=100&sortBy=market_cap&sortType=desc&convert=USD"
))

coins = resp['data']['cryptoCurrencyList']    # list of coin objects
total_available = resp['data']['totalCount']  # 8374 as of 2026-04-18

for c in coins:
    usd = next(q for q in c['quotes'] if q['name'] == 'USD')
    print(
        f"#{c['cmcRank']} {c['symbol']}: "
        f"${usd['price']:,.2f} | "
        f"MCap ${usd['marketCap']/1e9:.1f}B | "
        f"Vol24h ${usd['volume24h']/1e9:.1f}B | "
        f"24h {usd['percentChange24h']:+.2f}% | "
        f"CS {c['circulatingSupply']:,.0f}"
    )

Coin object fields

Top-level (c in the loop above):

code
id, name, symbol, slug, cmcRank, marketPairCount,
circulatingSupply, selfReportedCirculatingSupply,
totalSupply, maxSupply, isActive, lastUpdated, dateAdded,
quotes, isAudited, auditInfoList, badges

Per-quote fields (inside c['quotes'], filtered by name == 'USD'):

code
name, price, volume24h, volumePercentChange, marketCap,
percentChange1h, percentChange24h, percentChange7d,
percentChange30d, percentChange60d, percentChange90d,
percentChange1y, ytdPriceChangePercentage,
fullyDilluttedMarketCap, marketCapByTotalSupply,
dominance, turnover, lastUpdated

Query parameters

python
# Pagination
"?start=1&limit=100"        # page 1 of 100
"?start=101&limit=100"      # page 2

# Sort
"sortBy=market_cap"         # default
"sortBy=volume_24h"
"sortBy=percent_change_24h"
"sortBy=price"
"sortBy=circulating_supply"
"sortType=desc"             # or asc

# Currency conversion (affects quote prices returned)
"convert=USD"               # USD prices
"convert=BTC"               # BTC-denominated

# Filter by type
"cryptoType=all"            # default — coins + tokens
"cryptoType=coins"          # layer-1s only (633 results)
"cryptoType=tokens"         # ERC-20 etc.

# Filter by tag (DeFi, NFT, etc.)
"tagSlugs=defi"             # 2698 results
"tagSlugs=nft"

Path 2: Internal detail API (single coin, full stats)

Best for fetching one coin's complete data including ATH, ATL, 52-week high/low, volume ranks.

python
import json

# Look up by CMC coin ID (BTC=1, ETH=1027, XRP=52, SOL=5426, BNB=1839)
resp = json.loads(http_get(
    "https://api.coinmarketcap.com/data-api/v3/cryptocurrency/detail?id=1"
))
data = resp['data']
s = data['statistics']

print(f"Price:             ${s['price']:,.2f}")
print(f"Rank:              #{s['rank']}")
print(f"Market Cap:        ${s['marketCap']:,.0f}")
print(f"Volume 24h:        ${s['volume24h']:,.0f}")
print(f"Circulating Supply:{s['circulatingSupply']:,.0f}")
print(f"Total Supply:      {s['totalSupply']:,.0f}")
print(f"Max Supply:        {s['maxSupply']:,.0f}")
print(f"24h Change:        {s['priceChangePercentage24h']:+.2f}%")
print(f"7d Change:         {s['priceChangePercentage7d']:+.2f}%")
print(f"ATH:               ${s['highAllTime']:,.2f} on {s['highAllTimeTimestamp']}")
print(f"ATL:               ${s['lowAllTime']:,.4f} on {s['lowAllTimeTimestamp']}")
print(f"52w High:          ${s['high52w']:,.2f}")
print(f"52w Low:           ${s['low52w']:,.2f}")
print(f"MCap Dominance:    {s['marketCapDominance']:.2f}%")

All statistics fields

code
price, priceChangePercentage1h, priceChangePercentage24h,
priceChangePercentage7d, priceChangePercentage30d,
priceChangePercentage60d, priceChangePercentage90d,
priceChangePercentage1y, priceChangePercentageAll,
marketCap, marketCapChangePercentage24h,
fullyDilutedMarketCap, mintedMarketCap,
circulatingSupply, totalSupply, maxSupply,
marketCapDominance, rank, roi,
low24h, high24h, low7d, high7d, low30d, high30d,
low52w, high52w, low90d, high90d,
lowAllTime, highAllTime,
lowAllTimeChangePercentage, highAllTimeChangePercentage,
lowAllTimeTimestamp, highAllTimeTimestamp,
lowYesterday, highYesterday, openYesterday, closeYesterday,
priceChangePercentageYesterday, volumeYesterday,
ytdPriceChangePercentage, volumeRank, volumeMcRank,
volume24h, volume24hReported, volume7d, volume7d Reported,
volume30d, volume30dReported, turnover

Top-level data fields (beyond statistics)

code
id, name, symbol, slug, category, description, dateAdded,
volume, volumeChangePercentage24h, cexVolume, dexVolume,
urls (website, explorer, twitter, reddit, etc.),
tags, platforms, relatedCoins, wallets,
holders, watchCount, watchListRanking

Path 3: Global market metrics

python
import json

resp = json.loads(http_get(
    "https://api.coinmarketcap.com/data-api/v3/global-metrics/quotes/latest"
))
data = resp['data']
q = data['quotes'][0]   # USD quote (cryptoId=2781)

print(f"Total Market Cap:  ${q['totalMarketCap']/1e12:.2f}T")
print(f"Total Volume 24h:  ${q['totalVolume24H']/1e9:.1f}B")
print(f"Altcoin MCap:      ${q['altcoinMarketCap']/1e12:.2f}T")
print(f"DeFi MCap:         ${q['defiMarketCap']/1e9:.1f}B")
print(f"DeFi Vol 24h:      ${q['defiVolume24H']/1e9:.1f}B")
print(f"Stablecoin MCap:   ${q['stablecoinMarketCap']/1e9:.1f}B")
print(f"Derivatives Vol:   ${q['derivativesVolume24H']/1e9:.1f}B")
print(f"BTC Dominance:     {data['btcDominance']:.2f}%")
print(f"ETH Dominance:     {data['ethDominance']:.2f}%")
print(f"Active Cryptos:    {data['activeCryptoCurrencies']}")
print(f"Total Cryptos:     {data['totalCryptoCurrencies']}")
print(f"Active Exchanges:  {data['activeExchanges']}")
print(f"Active Pairs:      {data['activeMarketPairs']}")

# Yesterday comparison
print(f"\nMCap Yesterday:    ${q['totalMarketCapYesterday']/1e12:.2f}T")
print(f"MCap Change:       {q['totalMarketCapYesterdayPercentageChange']:+.2f}%")

Path 4: Historical OHLCV (candlestick data)

python
import json, time

now = int(time.time())

# Daily candles for BTC over last 7 days
resp = json.loads(http_get(
    "https://api.coinmarketcap.com/data-api/v3/cryptocurrency/historical"
    f"?id=1&convertId=2781&timeStart={now - 7*86400}&timeEnd={now}&interval=daily"
))
candles = resp['data']['quotes']   # list of OHLCV dicts

for candle in candles:
    q = candle['quote']
    print(
        f"{candle['timeOpen'][:10]} "
        f"O={q['open']:,.0f} H={q['high']:,.0f} "
        f"L={q['low']:,.0f} C={q['close']:,.0f} "
        f"V=${q['volume']/1e9:.1f}B MCap=${q['marketCap']/1e12:.2f}T"
    )

Candle quote fields: open, high, low, close, volume, marketCap, circulatingSupply, timestamp

Supported intervals: daily, 1h (hourly). 5m returns HTTP 500 — not supported.

convertId=2781 = USD. timeStart/timeEnd are Unix timestamps.

Path 5: Exchange market pairs for a coin

python
import json

resp = json.loads(http_get(
    "https://api.coinmarketcap.com/data-api/v3/cryptocurrency/market-pairs/latest"
    "?id=1&start=1&limit=10&sort=volume"
))
data = resp['data']
print(f"Total pairs for {data['name']}: {data['numMarketPairs']}")

for pair in data['marketPairs']:
    print(
        f"  {pair['exchangeName']:20} {pair['marketPair']:12} "
        f"${pair['price']:,.2f} Vol=${pair['volumeUsd']/1e6:.1f}M"
    )

Pair fields: rank, exchangeId, exchangeName, exchangeSlug, marketId, marketPair, category (spot/futures), baseSymbol, quoteSymbol, baseCurrencyId, quoteCurrencyId, price, volumeUsd, effectiveLiquidity, lastUpdated, volumeBase, volumeQuote, depthUsdNegativeTwo, depthUsdPositiveTwo, feeType, isVerified, type (cex/dex)

Path 6: Exchange listings

python
import json

resp = json.loads(http_get(
    "https://api.coinmarketcap.com/data-api/v3/exchange/listing"
    "?start=1&limit=20&sortBy=score&sortType=desc"
))
exchanges = resp['data']['exchanges']
for ex in exchanges:
    print(f"  {ex['name']:30} score={ex.get('score')} trafficScore={ex.get('trafficScore')}")

Exchange fields: id, name, slug, dexStatus, platformId, status, score, trafficScore, countries, fiats, filteredTotalVol24h

Path 7: Price conversion (cross-rate)

python
import json

# Convert 1 BTC → USD
resp = json.loads(http_get(
    "https://api.coinmarketcap.com/data-api/v3/tools/price-conversion"
    "?amount=1&id=1&convert_id=2781"
))
result = resp['data']
usd_price = result['quote'][0]['price']
print(f"1 {result['symbol']} = ${usd_price:,.2f} USD")

# Convert ETH → BTC
resp2 = json.loads(http_get(
    "https://api.coinmarketcap.com/data-api/v3/tools/price-conversion"
    "?amount=1&id=1027&convert_id=1"
))
btc_price = resp2['data']['quote'][0]['price']
print(f"1 ETH = {btc_price:.6f} BTC")

id = source coin CMC ID, convert_id = target currency CMC ID (2781=USD, 1=BTC, 1027=ETH, 825=USDT)

Path 8: News / articles

python
import json

# News for a specific coin
resp = json.loads(http_get(
    "https://api.coinmarketcap.com/content/v3/news?coins=1&limit=10"
))
for article in resp['data']:
    meta = article['meta']
    print(f"  [{meta['sourceName']}] {meta['title']}")
    print(f"    {article['createdAt'][:10]} — {meta['sourceUrl']}")

Article fields: slug, cover, assets, createdAt + nested meta with title, subtitle, sourceName, sourceUrl, language, type, status, id, createdAt, updatedAt, releasedAt

Omit coins= param for general crypto news. Supports limit up to observed 50+ without errors.

Path 9: NEXT_DATA from HTML pages

Use when you need data that isn't in the API (e.g. Fear & Greed index, CMC100 index, trending categories).

Main page (coinmarketcap.com/)

python
import json, re

html = http_get("https://coinmarketcap.com/")
m = re.search(r'<script id="__NEXT_DATA__"[^>]+>([\s\S]*?)</script>', html)
nd = json.loads(m.group(1))
props = nd['props']

# Global market metrics (same data as global-metrics API, faster from HTML)
gm = props['pageProps']['globalMetrics']
print(f"Total cryptos: {gm['numCryptocurrencies']}")
print(f"BTC dominance: {gm['btcDominance']:.2f}%")
print(f"Total MCap:    ${gm['marketCap']/1e12:.2f}T")
print(f"Total Vol 24h: ${gm['totalVol']/1e9:.1f}B")

# Spot prices for BTC/ETH/USD/SATS/BITS (the "ticker bar" data)
# props['quotesLatestData'] — 5 items with short field names
for q in props['quotesLatestData']:
    print(f"  {q['symbol']}: p={q['p']} p24h={q['p24h']:+.3f}%")
    # fields: id, symbol, p (price), p1h, p24h, p7d, p30d, p60d, p90d, pytd, t

# Top 101 coins with full USD quotes — from dehydratedState
queries = props['dehydratedState']['queries']
homepage_q = next(q for q in queries if q['queryKey'] == ['homepage-data', 1, 100])
listing = homepage_q['state']['data']['data']['listing']
coins = listing['cryptoCurrencyList']   # 101 coins
total = listing['totalCount']

for c in coins:
    if c['symbol'] == 'BTC':
        usd = next(q for q in c['quotes'] if q['name'] == 'USD')
        print(f"BTC: #{c['cmcRank']} ${usd['price']:,.2f}")
        break

# Page-level shared data (Fear & Greed index, CMC20, altcoin index)
psd = props['pageProps']['pageSharedData']
print("pageSharedData keys:", list(psd.keys()))
# keys: topCategories, fearGreedIndexData, cmc100, cmc20, faqData, altcoinIndex, halvingInfo, deviceInfo

Gotcha — regex pattern: Use [^>]+ to match the crossorigin="anonymous" attribute on the script tag. type="application/json" alone will miss it:

python
# CORRECT
m = re.search(r'<script id="__NEXT_DATA__"[^>]+>([\s\S]*?)</script>', html)

# WRONG — returns None because of crossorigin attr
m = re.search(r'<script id="__NEXT_DATA__" type="application/json">(.*?)</script>', html, re.DOTALL)

quotesLatestData has only 5 entries (SATS, BITS, BTC, ETH, USD) — it's the currency selector bar, not the full market ranking. For the full ranked listing use dehydratedState.

cmcRank is at coin top level, not inside the USD quote object. The cmcRank field inside the quote dict is None.

Individual coin page (/currencies/{slug}/)

python
import json, re

html = http_get("https://coinmarketcap.com/currencies/bitcoin/")
m = re.search(r'<script id="__NEXT_DATA__"[^>]+>([\s\S]*?)</script>', html)
nd = json.loads(m.group(1))

# All stats under props.pageProps.detailRes.detail.statistics
stats = nd['props']['pageProps']['detailRes']['detail']['statistics']

print(f"Price:     ${stats['price']:,.2f}")
print(f"Rank:      #{stats['rank']}")
print(f"MCap:      ${stats['marketCap']:,.0f}")
print(f"Vol 24h:   ${stats['volume24h']:,.0f}")
print(f"Circ Sup:  {stats['circulatingSupply']:,.0f}")
print(f"24h:       {stats['priceChangePercentage24h']:+.2f}%")
print(f"ATH:       ${stats['highAllTime']:,.2f} ({stats['highAllTimeTimestamp']})")
print(f"ATL:       ${stats['lowAllTime']:.4f}")

detailRes.detail also contains: name, symbol, slug, description, tags, urls (website/explorer/twitter/reddit), platforms, relatedCoins, holders, watchCount

Note: The currency page has no JSON-LD blocks — zero <script type="application/ld+json"> elements.

Common coin IDs

IDSymbolName
1BTCBitcoin
1027ETHEthereum
52XRPXRP
825USDTTether
1839BNBBNB
3408USDCUSD Coin
5426SOLSolana
74DOGEDogecoin
2781USDUS Dollar (for convert_id)

Find IDs from the listing API: c['id'] or from the detail API URL by looking up a slug first via the listing API's c['slug'] field.

Anti-bot / rate limits

Main site (coinmarketcap.com):

  • http_get works with the default Mozilla/5.0 UA — no Cloudflare, no bot detection triggered.
  • Page loads are ~700ms for 690–710KB of HTML+__NEXT_DATA__.

Internal API (api.coinmarketcap.com):

  • No auth headers required. No X-Request-Id or X-Forwarded-For needed.
  • 25 rapid sequential calls with zero rate limiting or errors — no throttle observed at that volume.
  • Typical latency: 65–250ms per call.
  • error_code: '0' and error_message: 'SUCCESS' in every response; no credit_count consumed.

v2 API (api.coinmarketcap.com/v2/):

  • Returns HTTP 401 Unauthorized — requires API key. Do not use.

Pro API (pro-api.coinmarketcap.com):

  • Paid, requires X-CMC_PRO_API_KEY header. Do not test or call.

Gotchas

  • No JSON-LD on any page tested — coin pages have zero <script type="application/ld+json"> elements. Don't look for schema.org markup.

  • __NEXT_DATA__ regex: Must use [^>]+ between __NEXT_DATA__" and > — the tag has crossorigin="anonymous" which breaks a naive type="application/json"> match.

  • cmcRank location on homepage listing: It's c['cmcRank'] (top-level), NOT inside c['quotes'][n]['cmcRank'] (that field is always None).

  • 5m/sub-hourly OHLCV not available: Interval 5m returns HTTP 500. Use 1h for sub-daily and daily for longer ranges.

  • v2 API is auth-only: api.coinmarketcap.com/v2/... requires API key (401). The equivalent data is available via data-api/v3/ without auth.

  • convert param accepts symbols not just IDs in the listing API, but convert_id in the price-conversion API requires numeric IDs (e.g. 2781 not USD).

  • Circulating supply: c['circulatingSupply'] at the coin top level in the listing response — not inside the quote. The quote has marketCap which equals price * circulatingSupply.

  • Multiple quotes per coin: The listing API returns multiple quote objects when you request multiple convert currencies. Always filter by q['name'] == 'USD' (or your target currency) before reading price fields.

  • Pagination: start is 1-indexed (not 0-indexed). start=1&limit=100 returns items 1–100, start=101&limit=100 returns items 101–200.