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About HTML Valid
Working with developer and design work no longer requires installing heavy desktop software — HTML Valid runs entirely in your browser, instantly. Processing runs locally in your browser using modern Web APIs. Nothing is uploaded, nothing is logged, and there is no quota to worry about for casual use. Like everything else in the developer collection, it is free, ad-light, and works on mobile as well as desktop.
When you'd reach for HTML Valid
You need to handle a one-off task right before a meeting and don't have time to install anything.
Anyone working remotely on a borrowed or restricted machine.
Open the page, get the result, paste it into your doc — under a minute.
You're on a public or shared machine and don't want to leave traces of what you're working on.
Travelers, contractors, anyone working from a friend's computer.
Nothing is uploaded, nothing persists if you're not signed in.
You're cleaning up a folder of files that accumulated over a project and need to standardize them.
Designers, writers, and developers wrapping up deliverables.
Drop each file in, copy the output, move on.
You're hitting the daily limit of a paid SaaS and need a backup option for a single quick job.
Marketers and ops people whose primary tool is metered.
Stay productive without burning credits.
Frequently asked about HTML Valid
- Is HTML Valid really free?
- Yes — HTML Valid is free for unlimited personal use, with no account required and no watermark on the output.
- Are my files uploaded to a server when I use HTML Valid?
- HTML Valid processes everything in your browser using local APIs. Your files never leave your device.
- Can I use HTML Valid commercially?
- Yes. The output of HTML Valid belongs entirely to you, with no licensing restrictions.
- Do I need to create an account to use HTML Valid?
- No. HTML Valid works without any signup. We only ask for an email if you decide to subscribe to a paid plan.
- Does HTML Valid work on mobile?
- Yes, HTML Valid is fully responsive and tested on iOS Safari and Android Chrome.