What's the difference between side-by-side and unified view?

Side-by-side view places the original and changed text in two columns for easy visual comparison. Unified view merges both into a single column with +/- markers, similar to a Git patch or pull request diff.

What do the colors in the diff mean?

Green highlights content added in B, red highlights content removed from A, amber/yellow marks lines that were changed, and unhighlighted lines are identical in both versions.

Diff Checker – Compare Text & Code Side-by-Side Online Free

Q: Is the diff checker free to use?

Yes, completely free. There are no limits, no accounts, no watermarks, and no charges. Compare as much text or code as you need.

Q: What algorithm does the diff checker use?

It uses the Myers diff algorithm, the same shortest-edit-script algorithm that powers Git's diff and merge tooling, to find the minimal set of changes between two texts.

Q: Does my text or code get uploaded to a server?

No. All comparisons run entirely in your browser using JavaScript. Nothing is transmitted to any server, so your content remains completely private.

Q: Can I ignore whitespace or case differences?

Yes. Toggle 'Ignore whitespace' to treat differing spacing/indentation as equal, and 'Ignore case' to treat uppercase and lowercase letters as identical when computing the diff.

// Features Why Use I7 Pixel's Free Diff Checker?

Whether you're reviewing a pull request, proofreading a contract, or checking what changed between two drafts, I7 Pixel's diff checker highlights every difference instantly — live in your browser, with no upload and no signup.

🔀

Line, Word & Character Diffs

Choose the comparison granularity that fits your content — compare whole lines, individual words, or down to single characters.

⧉

Side-by-Side & Unified Views

Switch between a two-column side-by-side layout for visual review or a unified patch-style view for a compact, Git-like diff.

🎨

Color-Coded Highlights

Additions, deletions, and changes are color-coded so you can scan large blocks of text or code and spot every edit at a glance.

🔇

Ignore Whitespace & Case

Toggle off whitespace-only or case-only differences when you only care about meaningful content changes, not formatting noise.

📦

Collapsible Equal Blocks

Long unchanged sections collapse automatically, with adjustable context lines (2, 3, 5, 10, or all) so you can focus on what changed.

🔬

Inline Character Highlighting

On modified lines, the exact words or characters that changed are highlighted inline — not just the whole line.

📊

Instant Diff Statistics

See line counts for both versions plus totals for added, removed, changed, and unchanged lines the moment you compare.

📋

One-Click Copy

Copy the full diff output to your clipboard in one click — handy for pasting into reports, tickets, or chat messages.

🔒

100% Private — No Upload

Every comparison runs locally in your browser using JavaScript. Nothing is transmitted to any server, so your text stays completely private.

// Guide How to Compare Text or Code Online — Step by Step

Comparing two versions of text or code takes just four steps.

1

Paste the Original Text

Paste or type your original text or code into the "Original (A)" panel on the left.

2

Paste the Changed Text

Paste or type the updated version into the "Changed (B)" panel, or try a built-in sample.

3

Click Compare

Press Compare or hit Ctrl/Cmd + Enter. A color-coded diff with line statistics appears instantly.

4

Review & Copy the Diff

Switch between Side-by-Side and Unified views, tweak the comparison options, and copy the result.

// Deep Dive Understanding Text & Code Comparison

A few core concepts make it easier to read and trust a diff result.

🧮

The Myers Diff Algorithm

This tool computes differences using the Myers diff algorithm — the same shortest-edit-script approach used internally by Git. Instead of just flagging "these two blocks differ," it finds the smallest possible set of insertions and deletions needed to turn the original text into the changed text, which is why the highlighted differences feel minimal and intuitive rather than noisy.

⧉

Side-by-Side vs Unified — Which Should You Use?

Side-by-side view places Original (A) and Changed (B) in two columns, which is great for visually scanning structural changes in documents, prose, or markup. Unified view merges both versions into a single column with + and - markers, similar to a git diff or a pull request patch — ideal when you want a compact view to paste into a code review or ticket.

🔬

Line, Word, and Character-Level Diffs

Line-level comparison is the default and best for code, configs, and structured text where each line is a discrete unit. Word-level comparison is useful for prose, where a single sentence might have a few words changed. Character-level comparison is the most granular — handy for short strings, IDs, URLs, or minified code where a single character can matter.

// Reference Diff Mode & View Comparison

Quick reference for choosing the right comparison mode and view for your content.

Mode / View	Granularity	Best Used For
Line-by-line Default	Whole lines	Source code, config files, structured or line-oriented text
Word-level	Individual words	Prose, essays, articles, and translated text
Character-level	Single characters	Short strings, IDs, URLs, minified or single-line code
Side-by-Side View Default	Two columns	Visual review of documents, contracts, and markup
Unified View	Single column	Compact, Git-style patches for code review and tickets

// Use Cases Who Uses a Diff Checker?

Comparing two versions of text or code is a daily task across development, writing, legal, and content workflows.

💻

Developers

Compare two versions of a file, snippet, or config without opening a full Git client — useful for quick reviews or debugging.

✍️

Writers & Editors

See exactly what changed between two drafts of an article, blog post, or manuscript at the word level.

⚖️

Legal & Contract Review

Spot every wording change between two versions of a contract, policy, or terms document before signing off.

🌐

Translators

Compare translation drafts or revisions side-by-side to verify edits without re-reading the entire text.

📄

Content & CMS Editors

Check what changed between two versions of page copy, JSON config, or HTML markup before publishing.

🎓

Students & Researchers

Compare essay drafts, citations, or data files to track revisions and confirm nothing was accidentally lost.

// FAQ Frequently Asked Questions

Answers to the most common questions about the diff checker.

Yes — completely free. There are no limits, no accounts, no watermarks, and no charges. Compare as much text or code as you need.

It uses the Myers diff algorithm — the same shortest-edit-script algorithm that powers Git's diff and merge tooling — to find the minimal set of changes between the two texts.

No — never. All comparisons run entirely in your browser using JavaScript. Nothing is transmitted, logged, or stored anywhere outside your device.

Side-by-side places A and B in two columns for visual comparison. Unified merges both into one column with +/- markers, similar to a Git patch or pull request diff.

Yes. Toggle Ignore whitespace to treat differing spacing or indentation as equal, and Ignore case to treat uppercase and lowercase letters as identical when computing the diff.

Green marks content added in B, red marks content removed from A, amber marks lines that were changed, and unhighlighted lines are identical in both versions.

// Reviews User Ratings & Feedback

Tried the tool? Leave a quick rating and help others find it.

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All tools at I7 Pixel run in your browser — no uploads, no accounts, always free.