Stop hallucinating numbers.

REST API

One POST. Eight engines evaluate it in parallel — eight different arithmetics, eight different failure modes.

curl -X POST https://ultimath.ai/api/v1/evaluate \
  -H "X-API-Key: $ULTIMATH_KEY" \
  -H "Content-Type: application/json" \
  -d '{"expression": "(1e16 + 1) - 1e16"}'

MCP, in any client

Claude, Cursor, VS Code, LM Studio and the CLIs call Ultimath themselves, whenever an answer has to be a number rather than a guess.

Install npm package