Compare two text files or PDFs. Line diff with inline character highlighting.
File A (original)
Drop file A
text · code · PDF
File B (changed)
Drop file B
text · code · PDF
Compare any two text-based files directly in your browser. Drop a file into slot A and slot B — the diff runs automatically. PDF files are supported: text is extracted using PDF.js before comparison. Changed lines show character-level inline highlighting. Long unchanged sections are collapsed for readability.
Any plain text file — source code, JSON, YAML, Markdown, CSV, config files, etc. PDF files are also supported (text is extracted first).
The diff is capped at 3,000 lines per file. Beyond that, lines are truncated and a warning is shown.
No. Text extraction and diffing run entirely in your browser. Nothing is sent to a server.
It uses Longest Common Subsequence (LCS) with a typed array to find the minimal edit distance between two sets of lines.
Keywords: file diff, compare files online, text diff, code diff, diff viewer browser, no upload diff tool