All free tools Runs in your browser

HTML Compare

Paste two versions of a page, template or config file and see every changed line and word side by side.

TWO VERSIONS

Compare HTML or text

Diff
Files are read locally with FileReader and never uploaded. Maximum 15 MB each. Press Ctrl + Enter to compare again.
Comparison options

Neither version leaves this device. The comparison runs in your browser. Nothing is uploaded to VPSLake or stored, so unpublished pages and client files stay private.

HOW TO USE IT

Compare two versions in four steps

Check a theme update, a CMS change, an edited template or two copies of a server config.

  1. 1

    Paste the original on the left

    Paste the old version, or open it from a backup file.

  2. 2

    Paste the new version on the right

    Paste the changed copy. To grab a live page, open it, press Ctrl + U and copy the source.

  3. 3

    Compare

    Press Compare. Removed lines are red, added lines are green, and inside changed lines the exact words that differ are highlighted.

  4. 4

    Narrow it down and share

    Tick the options to hide whitespace or case noise, then copy or download the unified diff for a ticket or a colleague.

It compares source, not the rendered page

The tool works line by line on the text you paste, so you see every changed tag, attribute, script and piece of copy, which is exactly what you need when checking what a plugin, a theme update or a teammate changed.

Because it is plain text comparison, it works just as well for CSS, JavaScript, PHP, JSON, YAML, nginx.conf, .htaccess or two drafts of an article.

Getting a cleaner diff

  • Use Ignore whitespace after a reformat or a change from tabs to spaces
  • Minified HTML is one long line; format both copies first so changes line up
  • For JSON, sort keys in the JSON formatter before comparing
  • On a server, diff -u old.conf new.conf gives the same unified format

FREQUENTLY ASKED QUESTIONS

HTML Compare FAQ

No. Both versions are compared by JavaScript in your browser. Nothing is sent to VPSLake or stored, which makes it safe for unreleased pages and client code.
A red line exists only in the original, a green line exists only in the changed version, and a line shown on both sides with highlighted words was edited. The shaded grey cell marks the side where the line does not exist.
Yes. View the live page's source with Ctrl + U and copy it to the right. Put your older copy from a backup, Git or the Wayback Machine on the left.
Usually the line endings, indentation or minification differ. Tick Ignore whitespace, or format both copies first so each tag sits on its own line.
Each file can be up to 15 MB. Very different large files take longer; if the two texts have almost nothing in common, the tool stops and asks you to check that you pasted matching versions.
A plain-text version of the result where removed lines start with - and added lines with +. It is easy to paste into an email, a chat or a support ticket.