Six engines. Your choice.
Pin Stockfish 14–19 for consistent version selection, or use latest to follow the current release.
Engine catalogue ↗Chess intelligence / Developer API
The engine.
Your next move.
World-class chess analysis, one HTTPS request away. Evaluate positions, find the best move, and analyze games with Stockfish 14–19.
Start with 100 free requests with a verified email, then add a card for 2,000 units/day and automatic overage billing. The trial is shared across your account, never resets, and is never charged. All prices are in USD.
POSITION INSPECTORSTARTPOS
01 / Integrate
From position
to evaluation.
Send a FEN. Get structured JSON with scores, best moves, and principal variations. Use REST in your stack, or connect an agent through MCP.
Explore the API reference →POST /v1/evalHTTPS / JSON
curl -s https://stockfishapi.com/v1/eval \
-H "Authorization: Bearer $STOCKFISH_API_KEY" \
-H "Content-Type: application/json" \
-d '{"engine":"stockfish-19","fen":"rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1","depth":8}'const res = await fetch("https://stockfishapi.com/v1/eval", {
method: "POST",
headers: { Authorization: `Bearer ${process.env.STOCKFISH_API_KEY}`, "Content-Type": "application/json" },
body: JSON.stringify({
"engine": "stockfish-19",
"fen": "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1",
"depth": 8
}),
});
const data = await res.json();import os, requests
r = requests.post(
"https://stockfishapi.com/v1/eval",
headers={"Authorization": f"Bearer {os.environ['STOCKFISH_API_KEY']}"},
json={
"engine": "stockfish-19",
"fen": "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1",
"depth": 8
},
)
data = r.json()02 / Capabilities
Built for your next chess project.
Positions to full games.
Evaluate one position or submit up to 50 in a batch. Analyze PGN games and follow job progress.
Read the documentation ↗Predictable usage.
Every search has a node budget. Quote units before you run a request; cached results cost zero units.
Usage and limits ↗Ready for your agents.
REST, OpenAPI, and MCP tools use the same authentication and quotas. Bring chess analysis to your workflow.
Connect an agent ↗Your next move
Start building for free.
2,000 units a day. Depth up to 14. All six engine versions.
Shared account allowance. Explore monthly plans for deeper analysis.