Text Compare & Diff Checker
Spot every difference in your text or code instantly — with full privacy.
No login, no upload, no noise. Processed entirely in your browser.
Compare text revisions without losing the details
Paste two drafts to find added, removed, and edited text. Switch between a side-by-side comparison and a unified diff, with the comparison processed in your browser.
How to Compare Two Texts
01.Paste your text
Paste your original draft on the left and the revised draft on the right.
02.Find differences
Select Find Differences to compare both versions. Use Try an example to load the sample below and open its diff.
03.Review the result
Switch between Split View and Unified View to review additions and removals alongside unchanged context.
Text comparison example
Our team ships updates every Friday.
The changelog is reviewed by two editors.
Deprecated features are removed after 90 days.
Customers are notified by email.Our team ships updates every Tuesday.
The changelog is reviewed by two editors.
New features are documented in the handbook.
Deprecated features are removed after 30 days.
Customers are notified by email.The example changes the release day, adds a documentation step, and shortens the deprecation window from 90 to 30 days. Unchanged sentences give you context around each edit.
Text Diff Tips
Normalize whitespace first
Trailing spaces and mixed tabs/spaces show up as changes even when the words are identical. If a diff looks noisier than expected, clean up whitespace before comparing.
Compare at the right granularity
Use Split View to scan long documents section by section, and Unified View when you want a compact changelog-style summary of edits.
Watch for smart quotes and invisible characters
Text copied from word processors often swaps straight quotes for curly ones or inserts non-breaking spaces. These show as changed words even though they look identical.
Before you compare
This compares the text you provide, including punctuation and whitespace. It does not check grammar or detect plagiarism.
Each side supports up to 250,000 characters or 5,000 lines. Compared contents stay in your browser. No account is required.
Working with another format? Try File Comparison Tool or Markdown Diff Tool.
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Frequently Asked Questions
Clear answers to your comparison queries.
DiffStack is a free online tool to compare two pieces of text or code side-by-side. It highlights additions and deletions instantly in your browser.
Yes. DiffStack runs entirely in your local browser environment. No text or code is ever sent to our servers, ensuring 100% privacy.
Yes. DiffStack is completely free with no registration or subscription. Each side supports up to 250,000 characters or 5,000 lines.
You can compare any plain-text content: source code (JavaScript, Python, Java, and more), JSON, XML, YAML, CSV, Markdown, SQL, HTML, CSS, or regular text and paragraphs.