TRUECALC

TrueCalc

A spreadsheet formula engine with Google Sheets conformance, for Rust, JavaScript/WASM, MCP, and (soon) a hosted API.

TrueCalc is a spreadsheet formula engine with Google Sheets conformance, for Rust, JavaScript/WASM, MCP, and (soon) a hosted API.

New here? Getting started installs the npm package and runs a formula in under a minute.

  • Tutorials — hands-on, build-it-yourself walkthroughs. Every step runs in your browser. Start here if you're new.
  • Learn — a beginner→advanced guide to spreadsheet formulas and workbooks with TrueCalc.
  • Reference — a page for every function (with a runnable widget), plus error codes, dialects, and the workbook schema.
  • Compare — side-by-side comparisons like VLOOKUP vs XLOOKUP vs INDEX/MATCH, with runnable examples.
  • By industry — functions grouped by the work you do: finance, operations, science, and more.
  • API — MCP tools and the hosted REST API.

New to spreadsheet formulas? Follow the Beginner path for an ordered journey.