Crypto market data API for developers and AI agents
Real-time prices, historical OHLCV, and technical indicators over REST, WebSocket, and MCP — built for AI agents. Pay per call via x402 with no account required.
AI Assistant · MCP Connected
How's Bitcoin doing today?
BTC is at $63,226.91, down 2.60% over the past 24 hours on $23.39B in volume — market cap is $1.27T, with RSI holding at a firm 64.92.
- RSI (14)
- 64.92
- SMA
- $64,345.72
- EMA
- $64,394.94
- VWAP 24h
- $64,089.59
- MACD
- 526.71
- Histogram
- -181.86
RSI near 65 sounds bullish — is the trend actually holding up?
Not quite — the MACD histogram just went negative (-181.86): the 526.71 line dropped below its 708.57 signal, a classic momentum-fade even as RSI stays elevated. Price under both the SMA and EMA backs that up — watch for a break below the VWAP ($64,089.59) to confirm.
Any news driving that?
Nothing BTC-specific in the feed right now — the pullback lines up with a broader risk-off tone across majors today, not an isolated catalyst. Worth watching whether that changes rather than treating this as asset-specific news.
Coverage
Priced per market, not just per asset
Every asset broken out across the exchanges and pairs that actually trade it, so you can see where a price comes from rather than a single blended number.
Assets tracked
Exchanges covered
Markets indexed
Market cap tracked
Price history back to July 2010 — starting from Bitcoin's first recorded price of $0.086.
Capabilities
One API surface, every way you need to reach it
REST for your backend, WebSocket for live feeds, MCP for AI agents — all backed by the same market data.
REST API
Assets, exchanges, markets, and conversion rates over plain HTTP endpoints — JSON in, JSON out.
WebSocket streaming
Subscribe to a live price feed over WebSocket instead of polling REST for updates.
Historical OHLCV
Open/high/low/close/volume series for backtesting and charting, going back over a decade for major assets.
Technical indicators
SMA, EMA, RSI, MACD, and VWAP computed server-side and returned pre-formatted.
Exchange & market data
Every exchange and trading pair broken out individually, not just a single blended price.
Agent-friendly endpoints
A dedicated `agentFriendly` namespace with compact, LLM-optimized responses — payable per call with no API key via x402.
MCP server
An open-source Model Context Protocol server (npx coincap-mcp-server) that connects any MCP-compatible AI assistant to the full API.
AI-native
Your AI already speaks crypto
Skip writing API glue code. Connect the CoinCap MCP server once and any MCP-compatible assistant can query prices, history, and technical indicators directly.
Connect
Add CoinCap to your AI assistant's MCP config. Works with Claude Desktop, and any other MCP-compatible client.
{
"mcpServers": {
"crypto-prices": {
"command": "npx",
"args": ["coincap-mcp-server"],
"env": {
"COINCAP_API_KEY": "your_coincap_api_key_here"
}
}
}
}Ask
Query market data in plain language. The assistant picks the right tool call and handles the parameters.
"What's bitcoin's RSI on the daily chart right now?" "Compare ETH and SOL 24h volume across exchanges" "Is MACD showing a bullish or bearish crossover for bitcoin?"
Get answers
The assistant gets back structured data straight from the API and turns it into a real answer.
{
"rsi": {
"rsi": 25.37,
"date": "2026-08-01T00:00:13.172Z"
}
}Pay-per-call
Keyless access, settled in USDC on Base
Ten agent-friendly endpoints accept payment directly over the x402 protocol — no signup, no dashboard, no API key. Point a wallet at the API and it pays for what it uses.
No account, no API key
The agentFriendly routes work without signing up. A wallet holding USDC on Base is the only credential.
Signed off-chain, no gas needed
Payments are authorized via EIP-3009 signatures, not on-chain transactions — the wallet needs USDC only, never ETH.
Discoverable by agents
Every payable route's 402 response carries x402 Bazaar discovery metadata, so agent marketplaces like x402scan can index and call it automatically.
{
"mcpServers": {
"crypto-prices": {
"command": "npx",
"args": ["coincap-mcp-server"],
"env": {
"X402_PRIVATE_KEY": "0x_your_wallet_private_key"
}
}
}
}Use a dedicated, low-balance wallet. Fund it with only what you intend to spend on API calls, and never reuse a wallet holding significant funds — this key is read by both the npm package and your AI client.
The 10 payable routes, priced from $0.002 to $0.01 per call based on response size:
Quickstart
One endpoint, any language, real data back
Every plan — including the free tier — includes an API key. Send it as a bearer token or an apiKey query param and call GET /v3/price/bysymbol/BTC.
curl "https://rest.coincap.io/v3/price/bysymbol/BTC" \ -H "Authorization: Bearer YOUR_API_KEY"
const res = await fetch('https://rest.coincap.io/v3/price/bysymbol/BTC', {
headers: { Authorization: 'Bearer YOUR_API_KEY' },
})
const { data } = await res.json()
console.log(data) // e.g. ["68421.55"]import requests
res = requests.get(
"https://rest.coincap.io/v3/price/bysymbol/BTC",
headers={"Authorization": "Bearer YOUR_API_KEY"},
)
print(res.json()["data"]) # e.g. ["68421.55"]Response
{
"timestamp": 1723232156000,
"data": ["68421.55"]
}Where to next
Pick up where this page leaves off
Pricing
Start free, scale by the credit
Prices shown are the annual-equivalent monthly rate. Or skip a plan entirely: stake MOR for free access, or pay per call with x402 and no plan at all.
Free
$0/mo
500 credits/mo
Builder
$24/mo
50,000 credits/mo
Growth
$64/mo
450,000 credits/mo
Professional
$180/mo
1,500,000 credits/mo
Enterprise
$400/mo
5,000,000 credits/mo
Billed monthly instead of annually costs more per plan.
Stake MOR to unlock a tier's limits without paying for it.
FAQ
Questions developers actually ask
Does CoinCap have a free API key?
Yes. The free tier includes 500 credits per month and 5 requests per minute, no credit card required — enough to build and test against before choosing a paid plan.
Does the CoinCap API support real-time WebSocket prices?
Yes, on the Growth plan and above. WebSocket lets you subscribe to a live price feed instead of polling REST for updates; the Free and Builder plans are REST-only.
Can I use the CoinCap API without an API key?
Yes, for a subset of endpoints. Ten agent-friendly routes accept x402 pay-per-call payment in USDC on Base instead of an account — a wallet is the only credential, and payments are signed off-chain so no gas is needed.
Does CoinCap have an MCP server for AI agents?
Yes. The open-source coincap-mcp-server package (npx coincap-mcp-server) connects Claude Desktop and any other MCP-compatible assistant to the full API, including technical indicators.
How far back does CoinCap historical price data go?
Back to July 2010, starting from Bitcoin's first recorded price of $0.086. Depth varies by asset — Ethereum's history, for example, only starts in March 2016.
How much does the CoinCap API cost?
Free to start. Paid plans run from $24/mo (Builder, billed annually) up to $400/mo (Enterprise) based on monthly credits and rate limits. MOR staking is an alternative to paying for a plan, and x402 pay-per-call needs no plan at all.
Ready to pull live market data?
Start on the free tier, no credit card required, or read the docs first.