What this is
toolpack.dev is a collection of small utilities for developers — encoders, formatters, generators, converters. The kind of thing you reach for a dozen times a week and would rather not install.
There are plenty of sites like this. Two things make this one different.
Everything runs in your browser
Every tool on this site is JavaScript executing on your own device. When you paste a JWT into the decoder, that token is decoded locally; there is no request carrying it anywhere. The same is true of the password generator, the hash generator, the JSON formatter and the rest.
This is not a privacy promise you have to take on trust — you can verify it. Open your browser's network tab, use any tool, and watch: no request goes out. Or disconnect from the network entirely; the tools keep working, because the page has everything it needs once it has loaded.
That architecture has a practical side effect. Because there is no upload step and no server doing the work, there is no file size limit imposed by us. A 40 MB file encodes as fast as your machine can manage.
A small number of tools genuinely cannot work this way — anything that has to ask the network a question, such as a DNS lookup. Those are marked clearly, and they are the exception.
Built for the way developers actually work
Pages open ready to use: the input is already focused, sample data is loaded, and the result updates as you type. There is no "Convert" button to hunt for.
Ctrl+K opens a command palette from anywhere on the site, so moving between tools takes one keystroke rather than a trip back to a menu. Abbreviations work — typing b64 finds the Base64 encoder.
The explanations under each tool are written rather than generated. If a page tells you why Base64 is not encryption, or why a cron expression with both day fields set fires more often than you expect, that is because those are the mistakes that actually cost people time.
Who makes it
toolpack.dev is built and maintained by a single developer. It is not a company, there is no team, and there is no funding round. That is why the tool list grows steadily rather than all at once.
If something is broken, wrong, or missing, the contact page is the fastest way to reach me. Corrections to the technical explanations are especially welcome — getting those right is the point.
How it is paid for
Running this site costs money: hosting, a domain, occasional time. The plan is to cover that with advertising, kept deliberately modest — no ads above a tool, no pop-ups, nothing that shifts the page while you are reading it.
If ads are not running yet when you visit, that is simply because the site is new.