Diff Checker — Compare Two Texts Online Free
Paste original and changed text (or load files) to see differences instantly. Diff Checker highlights added lines in green and removed lines in red, with side-by-side or unified view, word-level highlights, ignore-whitespace, swap, and copy diff — all private in your browser.
How it works
Open Diff Checker
Paste original text on the left and changed text on the right (or load files)
Review side-by-side or unified differences
Copy the diff or tweak options like ignore whitespace
FAQ
Is this Diff Checker free?+
Yes. Compare text online for free with no signup. Processing stays in your browser.
Can I compare code or files?+
Yes. Paste any text or load .txt, .json, .csv, .md, source files, and more. For structured JSON/CSV, try JSON Diff or CSV Diff.
What is side-by-side vs unified?+
Side-by-side shows original and changed columns aligned. Unified shows a single list with +/− markers like a classic diff.
Is my text uploaded?+
No. Comparison runs entirely in your browser — nothing is sent to our servers.
Related tools
JSON Diff
Compare two JSON documents
CSV Diff
Compare two CSV files
Smart Editor
Paste anything — auto-detect, format, convert
Encoders
Base64, URL & HTML encode / decode