Free · Instant · In-Browser

Text & Code Diff Checker

Compare two versions of any text or code side-by-side. Highlights added, removed and changed lines with inline word-level and character-level diff. Perfect for code reviews, document drafts and config changes.

Line-level DiffWord & Char Inline DiffSplit & Unified ViewIgnore WhitespaceIgnore CaseContext LinesSearch HighlightExport Diff
Samples:
Original
Modified
Inline:
↔️
Ready to compare

Paste text or code into both panels above or try one of the sample presets then click Compare.

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📝
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🔄
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Free Online Diff Checker Compare Text and Code

The TOOLBeans Diff Checker compares two versions of any text or code and shows exactly what changed between them. Paste an original and a modified version into the two panels, click Compare, and the tool highlights every difference: lines that were added appear in green, lines that were removed appear in red, and lines that were edited show inline highlighting of the specific words or characters that changed. It is built for code reviews, tracking edits between document drafts, checking configuration changes, and any time you need to know precisely how two pieces of text differ.

Under the hood it uses a longest-common-subsequence diff algorithm, the same family of algorithm that powers tools like git diff. This means it does not just compare lines position by position; it finds the longest sequence of lines the two versions share and reports only the genuine insertions, deletions and changes, so the result stays readable even when whole blocks have moved or been rewritten.

Everything runs entirely in your browser. Your text, code and any files you upload never leave your device and are never sent to a server, which makes it safe for proprietary source code, unpublished writing or confidential configuration. There is no account, no upload limit and no cost.

How to Compare Two Texts Step by Step

1
Add your two versions

Paste the original into the left panel and the modified version into the right, or click Upload on either side to load a file. You can also click a sample to see how it works instantly.

2
Set comparison options

Turn on Ignore Whitespace to skip formatting-only differences, or Ignore Case for case-insensitive comparison. Choose Word or Char inline granularity for how precisely changed lines are highlighted.

3
Click Compare

The tool runs the diff and shows the result. A stats bar summarises how many lines were added, removed, changed and left unchanged.

4
Choose a view

Switch between Split (side by side, like a code review), Unified (one column, like git diff), and Summary (statistics plus a change-distribution chart and a changed-lines-only list).

5
Focus on what matters

Turn off Show Unchanged to collapse identical sections, leaving only the changes plus a few lines of context that you can adjust. Use the search box to highlight a term across the whole diff.

6
Copy or export

Copy either the original or modified text, or export the full comparison as a unified diff .txt file you can attach to a review or commit.

Split, Unified and Summary Views

The same comparison can be viewed three ways, each suited to a different task. Switch between them at any time without re-running the diff.

⬛ Split View

The original and modified versions sit side by side in two columns, with changes aligned across them. This is the classic code-review layout and is best for reading two versions in parallel and seeing where each change lands.

☰ Unified View

Removed and added lines are stacked in a single column, prefixed with − and +, exactly like the output of git diff or a patch file. Best for a compact, top-to-bottom read and for content that is too wide for two columns.

📊 Summary View

A dashboard of the comparison: counts of added, removed, changed and unchanged lines, a visual distribution bar, text statistics, and a list showing only the changed lines. Best for a quick high-level sense of how much changed.

Word-Level vs Character-Level Inline Diff

When a line is edited rather than wholly added or removed, the tool shows an inline diff that highlights only the part that changed, instead of flagging the entire line. You can control how fine that highlighting is with the Inline toggle.

Word level highlights whole words that changed and is the most readable for prose and most code edits. Character level highlights individual characters, which is ideal for spotting a single-character difference such as a typo, a changed digit in a number, or a flipped operator like == to ===. Switch to Char when you need to find the smallest possible difference.

Two more options shape the comparison itself. Ignore Whitespace treats lines that differ only in spacing or indentation as identical, which is useful when reformatting has touched many lines but the logic is unchanged. Ignore Case compares text without regard to capitalisation, handy for case-insensitive content.

What People Use a Diff Checker For

👨‍💻 Code review

Compare an old and new version of a function or file to see exactly what a change does before merging or deploying it.

📝 Document drafts

Spot every edit between two versions of an article, contract, essay or report, down to the individual word.

⚙️ Config changes

Check what differs between two configuration or environment files to track down why an environment behaves differently.

🔁 Debugging output

Compare expected output against actual output, or two log files, to isolate exactly where they diverge.

📋 Copy-paste verification

Confirm that text was copied or migrated correctly by comparing the source against the destination.

🌐 Translations and content

Compare two language or content versions to ensure structure and key sections line up.

Your Text Stays Private

Many online diff tools send your text to a server to compute the comparison. This one does not. The entire diff algorithm runs locally in your browser using JavaScript, including reading any files you upload.

That matters when you are comparing proprietary source code, unpublished writing, legal documents or configuration that contains secrets. Because nothing is transmitted, you can compare sensitive material with confidence, and the tool keeps working even if your connection drops after the page loads.

Frequently Asked Questions

Is the diff checker free to use?+
Yes. It is completely free with no usage limits, no account and no signup. Every feature, including all three views, word and character inline diff, file upload and diff export, is available to everyone.
Does my text or code get uploaded to a server?+
No. All comparison runs entirely in your browser. Your text, code and uploaded files never leave your device, so it is safe for proprietary or confidential material.
What is the difference between split and unified view?+
Split view shows the two versions side by side in two columns, like a code review. Unified view stacks removed and added lines in a single column like git diff output. Summary view shows statistics and a change-distribution chart instead of the full text.
What does word-level versus character-level inline diff mean?+
On a changed line, word-level highlights the whole words that differ, while character-level highlights individual characters. Use word level for readability and character level to pinpoint a tiny change such as a single typo or a changed digit.
Can I ignore whitespace or letter case?+
Yes. Ignore Whitespace treats lines that differ only in spacing or indentation as equal, which is useful after reformatting. Ignore Case compares without regard to capitalisation. Both update the result immediately.
How do I hide the unchanged parts?+
Turn off Show Unchanged. The tool then collapses identical sections and shows only the changes plus a few lines of surrounding context, which you can set to 1, 3, 5 or 10 lines.
What file types can I upload?+
Plain text and common code and config formats including .txt, .js, .ts, .jsx, .tsx, .html, .css, .json, .xml, .md, .py, .php, .java, .sql, .yaml and more. Files are read locally in your browser.
Can I export or share the result?+
Yes. Use Export .txt to download the comparison in a unified diff format with − and + markers, which you can attach to a review, paste into a ticket, or keep as a record.
Does it work for very large files?+
It handles typical files comfortably. Because the comparison runs in your browser, extremely large inputs depend on your device, and the diff algorithm scales with the product of the two sizes, so very large files may be slower.
Is this the same as git diff?+
It uses the same core idea (a longest-common-subsequence diff) and the unified view mirrors git diff output, but it works on any pasted or uploaded text, requires no repository or version control, and adds word and character level inline highlighting on top.