About Ultimate Utilities

Ultimate Utilities is a free collection of 29 browser-based tools for everyday work: finance calculators, PDF and document conversion, image editing, audio and video processing, and utilities for developers.

Why so much runs in your browser

Most online tools work by uploading your file to a server. That is often unnecessary, and for anything sensitive — a salary figure, a proprietary stored procedure, a private document — it is a real cost. Wherever the work can be done with code running on your own machine, it is: the finance calculators, file and folder comparison, the JSON and hash tools, the Markdown viewer and the SQL flowchart all run locally in the browser and send nothing anywhere.

Some tasks genuinely need a server — video transcoding, OCR, PDF rasterisation. Those upload the file, process it, and delete it afterwards. Which is which is stated on the privacy page.

How it is built

The site is a Next.js frontend with a Python FastAPI backend. The calculators' underlying maths is a separate, dependency-free module with its own test suite, checked against published formulas and known values rather than against itself — money code that is quietly wrong by a few percent is worse than money code that crashes.

Cost

Everything is free to use, with no account, no sign-up and no usage limit. If advertising appears on the site, it is to cover hosting.

Accuracy

The finance tools project outcomes from assumptions you supply. They are a planning aid rather than a forecast, and are not financial advice — see the terms of use.