How to Compare Two Text Files Online

When you just need to know what changed

Two versions of a document. A “before” and “after” of some configuration. A draft and a revision. You know something changed — you just don’t know exactly what, or where. Reading both side by side is slow and your eye skips small edits. A proper text comparison shows you every difference, instantly.

Compare two text files in three steps

DiffALL makes it effortless:

Paste or upload both text files — paste mode works with no upload at all.
Get a line-by-line diff — equal, changed, inserted, and deleted lines, clearly marked.
Read a similarity score — a quick 0–100 headline for how close the two files are.

No install, free to start.

What you get

Line-by-line diff — see which lines were added, removed, or changed.
Character-level highlighting — within a changed line, the exact characters that differ are marked (green for matching, red for different), so a one-letter or one-digit edit is obvious.
Similarity score — quantify how close the two versions are at a glance.
Word Error Rate — useful when comparing paraphrased or machine-translated text.

Common use cases

Document revisions — compare two drafts to review every edit.
Config files — diff two versions before deploying to catch an accidental change.
Code snippets and logs — find the one line that’s different between a working and a broken file.
Translations and transcripts — measure how much two versions diverge.

More than plain text

The same engine handles JSON, CSV, XML, YAML, Markdown, and log files — with a structural diff for JSON and a clean line + character diff for the rest. Whatever you’re comparing, you get a clear answer instead of guesswork.

Try it now

Stop reading two files side by side hoping to catch the change. Paste them into DiffALL and see every difference in seconds.