Why do moved blocks show as remove and add?

Pure line diff does not track moves — reordering lines looks like deletions on one side and additions on the other. Use a dedicated merge tool or semantic diff for move detection.

What do “Trim lines” and “Ignore case” do?

They only change how lines are compared for equality (trim whitespace, or case-fold). The diff view still shows your original line text from each pane.

Where are my drafts saved?

Left and right text use localStorage keys droidxp-tdc-a and droidxp-tdc-b; checkbox state uses droidxp-tdc-opts. Clear removes all three keys and resets the compare options.

Can I diff entire files?

Paste file contents into the left and right editors. Very large pastes may slow the tab — consider comparing chunks or using a desktop tool for huge binaries.

Does the copied output match git diff?

It is a simple unified-style text with leading space, minus, or plus per line — similar in spirit, but not identical to git’s exact formatting or options.

Will Unicode or emoji break the diff?

Lines are compared as JavaScript strings. Surrogate pairs and combining characters count as part of the line; rare edge cases can compare differently than a byte-level Unix diff.

Is this suitable for secrets or regulated data?

Follow your policy. Nothing is sent to DroidXP, but shared screens and browser extensions can still leak content — avoid pasting production secrets into untrusted machines.

Text Diff Checker Online — Free Text Tool

What this text diff checker does

It splits each pane into lines, optionally normalizes them for comparison (trim whitespace and/or case folding), then runs a longest common subsequence (LCS) alignment. Matching lines stay neutral; lines only on the left are removed; lines only on the right are added. That is the same broad idea as many “unified” or “side‑by‑side” tools, tuned for fast in-browser review.

Line diff vs word or character diff

This page is intentionally line-oriented. If you change one word inside a long line, the tool typically shows that as removing the old line and inserting the new line. For fine-grained patches inside a line, use an editor plug-in or a dedicated diff engine — or break long lines before pasting.

Compare options

Trim lines when comparing: leading and trailing spaces are ignored when deciding if two lines match; displayed text is still your original line.
Ignore case when comparing: lines match if they are equal after lowercasing; display preserves original casing.

Privacy

Text is not sent to DroidXP. Optional localStorage keys droidxp-tdc-a, droidxp-tdc-b, and droidxp-tdc-opts store panes and checkbox state on this browser. Clear removes stored text for both panes, resets compare options, and clears the options key.

How to use this tool

Step 1: Paste the older or baseline text into Original (A) and the newer text into Modified (B).
Step 2: Toggle trim or ignore case if needed; read the colored preview and the live counts above.
Step 3: Use Copy unified diff for tickets or docs, or Swap sides to compare in the opposite direction.

Frequently Asked Questions

Does DroidXP upload my text?

No. Diffing runs locally. Drafts may be saved in localStorage on this device only.

Is this character-by-character or line-by-line?

Line-by-line. A change inside one long line usually appears as deleting that line and adding a new line with the revised content.

Why do moved paragraphs look like delete + add?

Line diff does not detect moves — reordering reads as removals on one side and additions on the other. Semantic or merge tools can sometimes infer moves.

What do “Trim lines” and “Ignore case” affect?

Only equality checks between lines. The preview still shows the exact text you pasted in each pane.

Where are drafts saved?

Left and right buffers use droidxp-tdc-a and droidxp-tdc-b; options use droidxp-tdc-opts. Clear empties both panes and removes all three keys.

Can I diff whole files?

Paste contents here. Very large files may slow the tab — split into sections or use a desktop diff for multi-megabyte binaries.

Is copied output the same as git diff?

It uses a simple unified-style line prefix ( , -, +). It is not a byte-for-byte match to git’s output or options.

Will Unicode or emoji work?

Generally yes — lines are JavaScript strings. Extremely unusual combining sequences may compare differently than a byte-level tool.

Should I paste production secrets here?

Even though nothing is uploaded, shoulder surfing and browser extensions remain risks. Follow your org’s policy for sensitive data.

Text Diff Checker