What kind of diff is this?

It is a line-based text comparison (unified-style highlighting). Entire lines are marked added or removed; it does not highlight word- or character-level edits inside a long line.

Can I compare code or config files?

Yes. Paste code, YAML/JSON configs, env samples, SQL, logs, or any plain text. Format both sides the same way first if whitespace-only noise would drown real changes.

Does it merge or resolve conflicts?

No. It only highlights differences. You still apply or resolve changes elsewhere.

No. Comparison runs locally in your browser.

Utill.net

Text Diff Checker

Side-by-Side Compare

Compare two texts line by line with live add/remove highlighting. For configs and patches—free online, no signup, browser-only.

This conversion runs only in your browser — nothing is uploaded.

Added+0
Removed−0
Lines0

Include +/- in copy

Original

Modified

Diff

Output...

What is this tool?

This text diff checker compares two plain-text blocks with a line-based algorithm. Unchanged lines stay neutral; removed lines are highlighted one way and added lines another—similar to a lightweight unified view without opening a full IDE.

It is built for quick reviews of configuration snippets, patch drafts, formatted JSON/YAML, SQL, env examples, and logs. It is not a word-level or character-level diff, and it does not merge conflicts or apply patches.

Use it before committing, filing a ticket, or sharing “what changed” with someone who only needs the delta.

Common use cases

Spot a single key change in a YAML/JSON config or .env sample
Review a short patch or release-note draft against the previous wording
Confirm that reformatting did not alter meaningful lines before you paste into production

How to use

Paste the original text on the left (Original) and the changed text on the right (Modified).
The diff updates live as you type (debounced). On mobile, use the Left / Right / Diff tabs.
Read the +added / −removed counts above the result.
Copy the result as plain lines, or turn on Include +/- in copy for a marker-prefixed paste. Sample loads a config-style pair; Clear resets both sides; Swap exchanges them.

Examples

Original	Modified	What you see
`timeout: 30`	`timeout: 60`	One removed line, one added line (same key, new value).
Three-line config without `region`	Same config plus `region: us-east-1`	One added line; others unchanged.
`alpha` / `beta`	`alpha` / `gamma`	`beta` removed, `gamma` added (Sample pair shape).
`hello world` (one line)	`hello there` (one line)	Whole line treated as remove+add—not a word-level highlight on `world`→`there`.

Practical pitfalls

Line-only granularity: editing one token in a long line marks the entire line removed and added. Split long lines or use a word-level tool when you need intra-line detail.
Trailing spaces and newline style (\n vs \r\n) count as real differences—normalize first if that noise hides the real change.
This page does not apply patches, three-way merge, or ignore-whitespace modes.

References

Last reviewed: 2026-07-27

Frequently asked questions

What kind of diff is this?: It is a line-based text comparison (unified-style highlighting). Entire lines are marked added or removed; it does not highlight word- or character-level edits inside a long line.
Can I compare code or config files?: Yes. Paste code, YAML/JSON configs, env samples, SQL, logs, or any plain text. Format both sides the same way first if whitespace-only noise would drown real changes.
Does it merge or resolve conflicts?: No. It only highlights differences. You still apply or resolve changes elsewhere.
Is my text uploaded?: No. Comparison runs locally in your browser.