Text Diff
Compare two pieces of text and see exactly what changed — added, removed, and edited lines, with word-level detail — entirely in your browser.
A text diff tool compares two pieces of text and highlights exactly what changed — added, removed, and edited lines, with word-level detail. 99digest’s diff runs entirely in your browser, so both documents stay on your device.
How this works
Paste your original text into the first box and the changed version into the second, then click Compare. The tool finds the smallest set of line-level changes between the two texts, then refines any changed line pair down to the specific words that differ — so a one-word edit shows as a one-word highlight, not a whole line marked as different.
How does it detect changes?
The tool compares line by line first, then within any line that changed, compares word by word — so you see exactly which words were added, removed, or edited, not just that “something changed” on that line.
Are my documents uploaded anywhere?
No. Both pieces of text are compared entirely in your browser — nothing is ever sent to a server, uploaded, or stored.
Does it compare at the word or character level?
Word level, within any line that changed. Unchanged lines are shown as-is, and changed lines show exactly which words differ.
Can I ignore formatting or whitespace differences?
Yes — use the “Ignore case,” “Ignore whitespace differences,” and “Ignore empty lines” options above the Compare button to focus only on meaningful changes.
Can I compare Word documents or PDFs directly?
Not yet — paste the text content from those files for now. Direct file comparison may be added in the future.
Is there a size limit?
Each side is limited to 1 MB of text, which comfortably covers documents, articles, and most code files.