HTML compare online — see exactly what changed
Paste two versions of an HTML page, template or any text and get a side-by-side diff. Added, removed and changed lines are highlighted down to the word, with options to ignore whitespace and case. Runs entirely in your browser.
Everything happens in your browser with JavaScript. Nothing you paste is sent to HostKarle or anyone else, so it is safe for API responses, config files and other private data. Shortcut: Ctrl + Enter runs the tool.
How to compare two HTML files
A theme update broke the header, a plugin started adding scripts, a freelancer "only changed one line". A diff shows what really happened in seconds.
Paste both versions
Original on the left, changed on the right. Paste from a file, your editor, a backup or the browser's View Source (Ctrl + U), or load the files directly.
Choose what to ignore
Hide noise from re-indented code with "Ignore whitespace", and turn on "Only changes" for long files so you scroll only through the differences.
Read the diff
Red is removed, green is added, and changed lines show the exact words that differ. The counters at the top tell you how many lines changed in total.
Frequently asked questions
Something not working the way you expect? Message us on WhatsApp at +91 94343 44325. We are a hosting company, so we answer developer questions too.
How do I compare two HTML files online?
Paste the original HTML in the left box and the changed HTML in the right box, then press Compare. The result shows both versions side by side: removed lines in red, added lines in green, and changed lines with the exact words that differ highlighted.
Does it compare the code or the rendered page?
The code. It compares the HTML source line by line, so you see every changed tag, attribute and piece of text. That is what you need when checking a template edit, a CMS update, a theme change or what a plugin injected into your page.
Can I compare plain text, CSS, JavaScript or JSON too?
Yes. The tool works on any text, so it doubles as a general text compare and diff checker for CSS, JS, PHP, config files, JSON or two versions of an article. For JSON, run both through the JSON formatter with "Sort keys" first so the same keys line up.
What do the options do?
"Ignore whitespace" treats lines as equal when only spaces, tabs or indentation differ, which hides reformatting noise. "Ignore case" treats <DIV> and <div> as the same. "Ignore blank lines" skips empty lines. "Only changes" collapses long runs of identical lines and keeps two lines of context around each change.
Is my HTML uploaded to a server?
No. The diff is calculated by JavaScript in your browser. Neither version is sent to HostKarle or anyone else, so it is safe for unpublished pages and client work.
How do I compare a live page with an older copy?
Open the live page, press Ctrl + U to view its source, select all and copy it into the right box. Paste your older copy (from a backup, Git or the Wayback Machine) into the left box and compare.
Can I save the result?
Yes. Press "Copy as unified diff" to copy a plain-text version with - and + markers that you can paste into a ticket, an email or a chat with your developer.
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