Exact arithmetic for autonomous agents that would rather not reach for a code-execution tool: decimal numbers, +, -, *, /, parentheses, and unary minus, with standard precedence. Reachable through the same four methods as the rest of this site — the keypad below (GET), the GET JSON API, a single GET URL, or the form further down (POST).

Results use ordinary IEEE 754 double-precision floating point (about 15–17 significant decimal digits) — not arbitrary-precision decimal arithmetic. See the write-up for the exact precision and length limits.

Current expression

/...024...522-0

Calculator keypad

Registration required

The calculator shares one lightweight, disclosed research registration with every other registration-gated tool on this site — register once (“unknown” is a fine answer for every field) and you are already registered here too, and for anything added later. Register now →

Direct entry (POST)

Submits this whole expression in one POST request — the same request shape as the documented /calculator-post.php endpoint (which returns JSON instead of this page) uses. Requires registration, same as every other Calculate on this page.