Diff Checker
Paste two versions and instantly see the differences, line by line. Added lines in green, removed in red — nothing uploaded.
Reviewed by the CalcCafe editorial team · Last updated 1 July 2026 · How we test our tools
No differences — the two texts are identical. added · removed
How it works
The two inputs are compared with a longest-common-subsequence algorithm that finds the smallest set of line additions and deletions, then renders them as a unified diff — all locally.
100% client-side — nothing you paste is ever uploaded.
Frequently asked questions
What kind of diff is this?
A line-by-line comparison, like a git diff. Added and removed lines are highlighted, with unchanged lines kept for context.
Is my text uploaded?
No — the comparison runs entirely in your browser, so it's safe for private code and documents.
People also ask
What is the best diff tool?
It depends on the job: for quickly comparing two pasted snippets, a browser-based tool like this one is fastest; for tracked files, git diff and your editor's built-in compare view are standard; and for merging, a three-way tool such as Meld, Beyond Compare, or KDiff3 helps. Most of them rely on a longest-common-subsequence style algorithm, as this tool does, to find the smallest set of added and removed lines.
Is there a diff tool in VS Code?
Yes, VS Code has a built-in diff view. Select two files in the Explorer, right-click, and choose Compare Selected, or run File: Compare Active File With from the Command Palette. The Source Control panel also opens a diff of any changed file against the last commit, and you can paste two texts into untitled tabs and compare those the same way.
Is there a PDF diff tool?
This tool compares text, so you can copy the text out of two PDFs, paste each version, and see the line-by-line changes. That works well for contracts and documents whose wording changed but ignores layout and images. Adobe Acrobat's Compare Files feature and some dedicated PDF tools compare visually as well as textually.
What is a good database diff tool?
For schema changes, export both schemas as SQL text (for example with pg_dump --schema-only or mysqldump --no-data) and paste the two dumps here or into any text diff to see which tables, columns, or indexes changed. Database IDEs such as DataGrip, DBeaver, and SQL Server Data Tools include schema compare features that also generate migration scripts. Migration tools like Flyway or Liquibase avoid the problem by tracking changes as versioned files.
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Sources & references
These tools follow our methodology and provide educational estimates only — verify important figures with a qualified professional.