Diff Viewer
Paste two blocks of text or JSON. See exactly what changed, line by line. JSON pretty-printing and whitespace-tolerance toggles included.
Left (before)
Right (after)
{"name": "Pyrelo",− "plan": "starter",− "seats": 5,+ "plan": "growth",+ "seats": 30,"features": ["tasks",− "chat"+ "chat",+ "payroll"]}
Diff is computed locally with an LCS algorithm. Both inputs stay in your browser.
FAQ
Is my text uploaded?▼
No. The diff is computed in your browser via a longest-common-subsequence algorithm. Both inputs never leave the page.
What's the difference between unified and split view?▼
Unified stacks the diff in one column (like `git diff`). Split shows the left text and right text side-by-side with aligned hunks — easier to scan large changes.
Does it diff JSON intelligently?▼
We line-diff after pretty-printing JSON if both sides parse. Toggle 'Treat as JSON' to enable that. Otherwise we treat input as plain text and diff line-by-line.
How big can my inputs be?▼
Comfortably up to ~3000 lines per side. The LCS algorithm scales by lines × lines, so very large diffs (10k+ lines) may be slow.
More Website Tools
HTTP Headers Inspector
Inspect response headers, the full redirect chain, and a security-header score (HSTS, CSP, X-Frame-Options) for any URL.
WHOIS Lookup
See a domain's registrar, registration date, expiry, status flags, and nameservers. Powered by RDAP — the modern WHOIS replacement.
JWT Decoder
Paste any JSON Web Token to see its header and payload, claims, and expiry countdown. Runs in your browser — nothing uploaded.