About Cloistr

Cloistr is a small, independent set of free online tools built for freelancers and small businesses — the kind of everyday calculations and utilities you need but shouldn't have to pay for or sign up to use.

It's built and run by one person, Hamza. No team, no funding, no investors — just a straightforward goal: make the tools freelancers and small business owners reach for constantly (VAT calculators, invoice generators, tax estimators, and more) fast, free, and actually pleasant to use.

What Cloistr is for

Running a small business or freelancing involves a long tail of small, repetitive tasks: working out VAT, estimating tax owed, generating an invoice, checking a profit margin, creating a strong password. None of these need an account, a subscription, or your personal data. Cloistr exists to handle them in a few seconds and get out of your way.

How it's built

Every tool on Cloistr runs entirely in your browser. There's no backend processing your numbers and no database storing what you type in — the moment you close the tab, it's gone. That's not a marketing line, it's just how the site is built: static pages, client-side calculations, nothing sent to a server. You can read more about exactly what is and isn't collected in the privacy policy.

How it stays free

Cloistr is supported by advertising and, eventually, a small number of relevant affiliate links — never by selling your data, and never by putting core tools behind a paywall. The tools stay free. That's the whole model.

Get in touch

Found a bug, have a tool you wish existed, or just want to say hello? Reach out at hello@cloistr.io.

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Sixteen free tools and counting — calculators, generators, and converters built for freelancers and small businesses.

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