See what changed between two versions of a text
Pick the granularity and view that show the changes best, learn to read a diff and compare PDFs too, with nothing uploaded.
To see what changed between two versions of a text, paste the original on one side and the revised one on the other, and the tool marks what was removed, what was added and what stayed. The text diff runs in your browser, which matters because the things people compare tend to be things that shouldn't leave their machine: a contract, a config file with keys in it, unreleased code.
How to compare two versions, step by step
- Open the text diff and paste the original into the Original panel and the new version into Modified. You can also load a file into each.
- Choose what to ignore: whitespace or letter case, if those changes don't matter to you.
- Choose the level of detail: lines, words or characters.
- Choose the view: side by side, unified or inline.
- If you need a record, export the result as Markdown.
Swap the two sides with Cmd+K, handy when you pasted the versions the wrong way round.
Reading a diff
In the unified view each line carries a prefix. A - marks something in the original that is gone, and a + marks something new. For example:
- Payment is due within 30 calendar days.
+ Payment is due within 45 business days.Read it like this: the line changed, and instead of 30 calendar days it now says 45 business days. In word mode the tool highlights just 30 and 45, and calendar and business, rather than flagging the whole line as different. That's why you switch to words or characters when lines are long.
Lines, words or characters?
| Level | Best for | Limit |
|---|---|---|
| Lines | Code, config files, lists | A line with a tiny edit is flagged whole |
| Words | Contracts, prose, emails | Ignores line structure |
| Characters | Catching a typo or a one-letter change | Can be noisy on long text |
Word and character modes display inline, and line mode offers the side-by-side or unified view.
Can you compare two PDFs or two Word files?
The tool compares text, not formatting. For two PDFs, extract the text of each with Extract Text from PDF and paste the two results. That only works when the PDFs have real text rather than scans, as covered in can't copy text from a PDF?. For Word, copy the document text. You lose bold, tables and comments, yet keep the wording, which is what changes in a contract.
Tips for a diff that helps
- Normalize before comparing. If one version uses tabs and the other spaces, everything looks different. Switch on Ignore whitespace, or format both versions with the same tool.
- Sort lists. Two lists with the same items in a different order produce a huge diff. Sort them first with Text Cleaner.
- Compare the minimum. If only one section matters, paste only that. A short diff is easier to review.
- Use words for prose and lines for code. Switching the level of detail is often what turns a confusing result into a clear one.
A typical config case:
image: nginx:1.25
- replicas: 2
+ replicas: 3The line without a prefix didn't change, and the important edit, going from two replicas to three, stands out without reading the whole file.
What a diff can't tell you
- Moved paragraphs. If you move a paragraph, it shows as removed in one place and added in another, not as "moved".
- Formatting changes. A different font, color or size doesn't exist in the text.
- Meaning. A diff says what changed, not whether it matters. A
30swapped for a45is tiny on screen and large in a contract.
Where people use it
Checking contract versions before signing, seeing what changed in a config file before a deploy, comparing two translations or two drafts of ad copy, and working out what a colleague edited in a shared document. If your files are YAML or JSON, run each version through the YAML formatter or JSON formatter first, so indentation differences don't show up as changes. And if you need to sort a list before comparing, remove duplicate lines and sort a list.
Frequently asked questions
How do I compare two texts to see the differences?
Paste the original in one panel and the new version in another. The tool colors what was removed, what was added and what didn't change, and you can view it side by side or in one column.
What do the + and - mean in a diff?
The minus sign marks what was in the original and is gone. The plus sign marks what was added in the new version.
Can I compare two PDFs?
Yes, if they contain real text. Extract the text of each PDF and compare the results. It doesn't work on scans, because they hold no text.
Can I ignore whitespace or letter case?
Yes. There are options to ignore whitespace and to ignore the difference between upper and lower case.
Are my texts uploaded to a server?
No. The comparison is computed in your browser.
Can I save the result?
Yes, you can export it as Markdown to keep a record of the changes.
Compare two versions now
By lines, words or characters, side by side or unified, with nothing uploaded. Runs locally, free, no signup.
Open Text Diff →Related tools
- Text Diff: lines, words or characters, with three views.
- Extract Text from PDF: pull the text from each PDF before comparing them.
- Text Cleaner: sort and de-duplicate before comparing lists.
- YAML Formatter: normalize indentation in config files.
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