Developer Tools
Small, exact tools for the jobs that come up every day. Each one runs inside your browser, so the token or config file you paste in never leaves your device.
Encode and decode
Convert data formats
Generate files
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How these tools handle your data
Your data never leaves your device
Converted by your browser and copied straight to your clipboard or downloads. Nothing is transmitted, nothing is stored.
Free, with no paid tier above it
No account, no watermark, no daily limit. There is no smaller version of these tools being held back.
No upload, no queue
Output appears as you type. There is no transfer to wait through and no queue to join.
Why paste-it-anywhere tools are a risk
The values developers convert are rarely harmless. A URL can hold a session token or a signed download link. A Base64 blob is often a key, a certificate or a JSON web token. An XML file might be a real invoice with real customer names in it. Most free converters post all of that to their own server to do the work, which quietly turns a thirty-second job into a disclosure.
Every tool on this page does the work locally instead, which is also why it is fast: there is no round trip to wait for. Encoding is still not encryption, though. Anything encoded here can be decoded by anyone who sees it, so treat these tools as plumbing rather than protection.
Frequently asked questions
Do these developer tools send my data to a server?
No. Each tool does its work in your browser on your own device. That matters more here than for most tools, because the things developers paste into a converter tend to be API keys, session tokens, invoices and config files. None of it is transmitted, so none of it ends up in someone else's logs.
Which tools are here right now?
Base64 encoding and decoding, URL percent-encoding and decoding, an XML to JSON converter, and a robots.txt generator that checks the file as you build it. Each one is a full page rather than a box on a shared page, so it handles the awkward cases properly: UTF-8 and emoji, the URL-safe Base64 alphabet, the three different URL encoding rules, XML attributes and repeated elements, and the difference between an empty Disallow line and one with a slash after it.
Is there a size limit?
Only what your own device can comfortably hold. There is no upload, so there is no upload limit and no queue to wait in. The practical ceiling is your available memory, which is far higher than the few kilobytes these tools are usually given.
Do they work offline?
Once a tool page has loaded, the conversion itself needs no connection at all. You can lose your network and keep working, because the code that does the job is already on your device.
Is encoding the same as encryption?
No, and it is worth being blunt about it. Base64 and percent-encoding are both trivially reversible by anyone who sees the result, with no key and no password. They exist to move data safely through a text-only path, not to hide it. If something genuinely needs protecting, encrypt it first and encode the result afterwards.
Do I need an account or an install?
No. Every tool runs in a normal browser on a phone, tablet or computer. There is nothing to install, no extension, no sign-up and no watermark on anything you download.