HeroTools / Productivity
Local · Private · Free

Mini Spreadsheet

A real spreadsheet with a working formula engine — type =SUM(B2:B5) and it just works, entirely on your device.

A1 fx
Click a cell, then type. Formulas start with = ↑↓←→ move · Enter ↓ · Tab → · Del clears

Your sheet is saved only in this browser (localStorage) — nothing is ever uploaded.

A spreadsheet that runs on your machine

Reference cells like A1, ranges like A1:B5, and combine them with + − * / ^ %. The formulas are parsed by a real tokenizer and recursive‑descent evaluator (no eval()), dependents recalculate automatically, and circular references are caught and flagged #CIRC!.

SUMAVERAGE / AVGMINMAXCOUNTCOUNTA IFROUNDABSSQRTPOWERMOD CONCATLENUPPERLOWERTODAYNOW

About Spreadsheet

Spreadsheet is a free, private productivity tool that runs entirely in your web browser. A mini spreadsheet with formulas (=SUM, =A1*B2…) and CSV import/export — runs locally. Because everything happens locally on your device, your files and data are never uploaded to a server, there is no sign-up or installation required, and it keeps working offline. It is handy for spreadsheet, excel, formula, grid. Like every HeroTool by Digital Heroes, Spreadsheet is 100% free with no limits.

How to use Spreadsheet

  1. Open Spreadsheet — it runs entirely in your browser, with no signup.
  2. Fill in the fields or choose the options you want.
  3. Adjust the options to match exactly what you need.
  4. Copy or download your result — it is free, and your data stays on your device.

Frequently asked questions

Is Spreadsheet free?

Yes — Spreadsheet is completely free for everyone. No sign-up, no account and no usage limits.

Is it private? Are my files uploaded anywhere?

No. Spreadsheet runs entirely in your browser on your own device, so your data never leaves your computer and nothing is uploaded to a server.

Does it work offline?

Yes. HeroTools is a Progressive Web App — once the page has loaded it keeps working offline, and you can install it as an app from your browser.

Do I need to install anything or create an account?

No. Just open the page and start using it. Installing it as an app is optional and only adds offline convenience.

What does Spreadsheet do?

A mini spreadsheet with formulas (=SUM, =A1*B2…) and CSV import/export — runs locally.

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