How Kalyvor keeps your files private
Encryption in transit, immediate deletion and what browser-side processing actually means.
4 min read
Developer utilitiesFree
HTML Validator
Check HTML for structural errors and accessibility warnings — unclosed tags, invalid nesting, duplicate ids, missing alt text and more.
- instantaverage
- In-browserprocessing
- Zerouploads
- Runs in your browser
- Nothing is uploaded
- No signup required
Developer utilities
HTML Validator
Input
Output
Enter HTML to validate.
Waiting for input
Paste, upload or type to begin.
Shortcuts⇧⌘CCopy output⌘LClear input
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Why Kalyvor
Built for people who value their time
Every formatters tool is fast, private and genuinely free — no dark patterns, no surprises.
Fast cloud processing
Jobs run on dedicated workers and finish in seconds — no queue, no spinner you can go make coffee to.
Auto file deletion
Everything you upload is erased the moment the job finishes. Nothing is written to long-term storage, so there is no retention period to wait out.
Works everywhere
Desktop, tablet or phone, any modern browser. Nothing to install, no plugins, no extensions.
Batch processing
Drop in a folder's worth of files and run the whole set through one tool in a single pass.
Privacy first
Encrypted in transit, never used to train models, never sold. Many tools never send the file at all.
No installation
Open a tab and go. No account needed to start, no download, no licence key to hunt for.
How it works
HTML Validator in three steps
No account, no installation, no manual. It takes about as long to do as it does to read.
- 01
Paste your HTML
Any HTML fragment or document.
- 02
Read the validation result
A pass/fail verdict plus every error and warning, updated instantly.
Questions
Frequently asked questions
Everything worth knowing before you run your first HTML Validator job. Still stuck? Talk to support.
Helpful articles
Guides and walkthroughs for getting more out of HTML Validator.
Batch processing: run 100 files at once
A practical walkthrough of queueing large jobs without babysitting the tab.
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Choosing the right tool for the job
A short decision guide for when two tools look like they do the same thing.
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Getting started with Kalyvor
From first upload to finished download in under a minute — the whole flow.
3 min read
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