About zztools.org
Last updated: September 2026
zztools.org is a small, independently run collection of online utilities for everyday file and text work: converting and resizing images, merging, splitting and encrypting PDFs, checking an IBAN, generating a UUID. There are 43 tools here and none of them require an account.
It is built and maintained by a two-person team of web developers. We started it because the tools we used ourselves kept asking us to sign up, upload sensitive documents to servers we knew nothing about, or sit through three ad interstitials before letting us resize a photo. We wanted the opposite: open the page, get the result, close the tab.
Everything here — the tools, the guides, the design — is written by us. If a tool gives a wrong answer, we want to hear about it: the address below reaches a person, not a ticket queue.
Who runs this site
zztools.org is operated by a small independent team. There is no parent company, no investor and no data business behind it. The site is funded by advertising, which is why you see ads on tool pages — that is the only reason the tools can stay free and account-free. We do not sell user data, because we do not collect it; the details are in the Privacy Policy.
How the tools work
Most tools on this site run entirely in your browser. When you resize an image, merge a PDF or generate a UUID, the file never leaves your device: the work is done by JavaScript and WebAssembly on your own machine. You do not have to take our word for it — open your browser's developer tools, switch to the Network panel and watch for uploads while the tool runs. A few tools do need a server (the bank and IBAN lookups query public reference data), and those pages say so explicitly rather than hiding it in a policy document.
How the content is written and updated
The guides are written from primary sources. Algorithms are checked against our own implementations, format facts come from the specifications themselves, and anything that changes over time — document photo requirements, for example — carries an explicit note telling you to confirm it with the issuing authority. Every guide shows the date it was last reviewed, and when a tool changes, the guide describing it is updated in the same release.
Corrections and feedback
Found a mistake, a tool that returns the wrong result, or a guide that has gone out of date? Write to support@zztools.org. Factual corrections come first, and we answer every report.