Free Crypto API — Real-Time Bitcoin & Ethereum Prices Without CoinMarketCap's $79/Month Plan

#webdev #python #api #javascript

CoinMarketCap's free tier gives you 10,000 credits/month — sounds generous until you realize a single /v1/cryptocurrency/listings/latest call costs 1 credit per coin returned. Need top 100 coins? That's 100 credits per call, or ~3 calls per hour before you hit the wall.

I built a lightweight alternative on Cloudflare Workers that aggregates CoinGecko's public data with edge caching. Here's what it does and how to use it.

What You Get (Free Tier: 500 requests/month)

Real-time prices for Bitcoin, Ethereum, and 10,000+ altcoins
Market cap, 24h volume, price change percentages
Trending coins (what's hot right now)
Historical price data by date
Exchange listings
Global market statistics
Sub-100ms latency via Cloudflare's 300+ edge locations

Quick Start

Python — Build a Portfolio Tracker

import requests

API_KEY = "your-rapidapi-key"
BASE_URL = "https://crypto-data-api1.p.rapidapi.com"

headers = {
    "x-rapidapi-key": API_KEY,
    "x-rapidapi-host": "crypto-data-api1.p.rapidapi.com"
}

# Get prices for multiple coins at once
response = requests.get(
    f"{BASE_URL}/price",
    headers=headers,
    params={
        "ids": "bitcoin,ethereum,solana,cardano",
        "vs": "usd"
    }
)

prices = response.json()
print(prices)
# {
#   "bitcoin": {"usd": 67432.50},
#   "ethereum": {"usd": 3521.80},
#   "solana": {"usd": 178.40},
#   "cardano": {"usd": 0.612}
# }

# Calculate portfolio value
portfolio = {
    "bitcoin": 0.5,
    "ethereum": 3.2,
    "solana": 50,
    "cardano": 1000
}

total = sum(
    portfolio[coin] * prices[coin]["usd"]
    for coin in portfolio
    if coin in prices
)
print(f"Portfolio value: ${total:,.2f}")

JavaScript — Real-Time Price Ticker

const headers = {
  'x-rapidapi-key': 'your-rapidapi-key',
  'x-rapidapi-host': 'crypto-data-api1.p.rapidapi.com'
};

// Fetch trending coins
async function getTrendingCoins() {
  const res = await fetch(
    'https://crypto-data-api1.p.rapidapi.com/trending',
    { headers }
  );
  const data = await res.json();
  return data.coins?.slice(0, 5) || [];
}

// Get market overview
async function getMarketOverview() {
  const res = await fetch(
    'https://crypto-data-api1.p.rapidapi.com/global',
    { headers }
  );
  return res.json();
}

// Build a simple dashboard
async function updateDashboard() {
  const [trending, global] = await Promise.all([
    getTrendingCoins(),
    getMarketOverview()
  ]);

  console.log('=== Crypto Market Dashboard ===');
  console.log(`Total Market Cap: $${(global.data?.total_market_cap?.usd / 1e12).toFixed(2)}T`);
  console.log(`BTC Dominance: ${global.data?.market_cap_percentage?.btc?.toFixed(1)}%`);
  console.log('\nTrending:');
  trending.forEach(coin => {
    console.log(`  ${coin.item.symbol}: #${coin.item.market_cap_rank}`);
  });
}

updateDashboard();

All Endpoints

Method	Path	Description
`GET`	`/price`	Current prices for one or more coins
`GET`	`/coin/:id`	Full details (supply, ATH, description)
`GET`	`/search`	Search by name or ticker symbol
`GET`	`/trending`	Top trending coins right now
`GET`	`/markets`	Paginated market listings
`GET`	`/history`	Historical price on a specific date
`GET`	`/exchanges`	Top exchanges by volume
`GET`	`/global`	Total market cap, dominance, stats

Practical Use Case: Crypto Alert Bot

import requests
import time

API_KEY = "your-rapidapi-key"
headers = {
    "x-rapidapi-key": API_KEY,
    "x-rapidapi-host": "crypto-data-api1.p.rapidapi.com"
}

ALERT_THRESHOLDS = {
    "bitcoin": {"above": 70000, "below": 60000},
    "ethereum": {"above": 4000, "below": 3000},
}

def check_alerts():
    ids = ",".join(ALERT_THRESHOLDS.keys())
    r = requests.get(
        "https://crypto-data-api1.p.rapidapi.com/price",
        headers=headers,
        params={"ids": ids, "vs": "usd"}
    )
    prices = r.json()

    for coin, thresholds in ALERT_THRESHOLDS.items():
        price = prices.get(coin, {}).get("usd", 0)
        if price > thresholds["above"]:
            print(f"🚀 {coin.upper()} ABOVE ${thresholds['above']:,}: ${price:,.2f}")
        elif price < thresholds["below"]:
            print(f"⚠️  {coin.upper()} BELOW ${thresholds['below']:,}: ${price:,.2f}")
        else:
            print(f"  {coin.upper()}: ${price:,.2f} (normal range)")

# Check every 5 minutes
while True:
    check_alerts()
    time.sleep(300)

Pricing

Plan	Price	Requests/month	Rate Limit
Basic (FREE)	$0	500	1 req/sec
Pro	$5.99	50,000	10 req/sec
Ultra	$14.99	500,000	50 req/sec

Available on RapidAPI: Crypto Data API

Why Not Just Use CoinGecko Directly?

You can — but:

CoinGecko's free API has aggressive rate limits and frequent 429 errors
No guaranteed uptime SLA on the free tier
This API adds edge caching, so repeated requests (e.g., price tickers) don't burn your quota

For high-frequency use cases like trading bots or real-time dashboards, the caching layer alone is worth it.