Reviewing a contract or a policy
Spot the clauses added, removed or reworded between the version you sent and the one that comes back signed.
Text comparator
See the differences between two versions of a text so you can identify added, removed or modified lines more easily, without sending anything to a server.
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Result
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How does this tool work?
Compare two versions of a text to see at once which lines were added, removed or changed: a renegotiated contract, a proofread article, a configuration file, an updated list or a corrected translation. Paste the original version on the left and the modified version on the right: the result shows the whole text line by line, with a marker in front of each change. Both texts stay in your browser and are never sent to a server.
The comparison works line by line. The tool looks for the longest sequence of lines common to both versions, then classifies every other line as a deletion or an addition. This method, the one used by diff tools for source code, keeps the two texts aligned: a line inserted at the top of the document does not prevent the identical lines that follow from being recognised.
In the result, an unchanged line starts with two spaces, a deleted line with “-” and an added line with “+”. A modified line therefore appears as a deletion followed by an addition, so you can read the old and new wording one above the other.
Two lines are identical only if every character matches: a capital letter, a trailing space or a different apostrophe is enough to flag a change. Windows and Unix line endings, however, are harmonised before comparing, so a simple change of system does not create false differences. For very long texts, the core of the calculation switches to a position-by-position comparison to protect the browser’s memory.
How to use this tool
Paste the original version
Put the reference text in the “Original text” field.
Paste the modified version
Add the new version in the “Modified text” field, then run the comparison.
Read the markers
Go through the lines preceded by “-” and “+”, then copy or export the result if you need to share it.
Use cases
Checking a proofread
See what an editor actually changed in an article before approving their version.
Comparing two exports
Find the lines that differ between two exports of a list, a CSV file or a configuration.
Examples
One inserted line and one modified line
The preamble added at the top does not shift the comparison: clauses 1 and 3 are still recognised as unchanged.
Input
Original:
Clause 1: purpose
Clause 2: term
Clause 3: price
Modified:
Preamble
Clause 1: purpose
Clause 2: term of 12 months
Clause 3: priceResult
+ Preamble
Clause 1: purpose
- Clause 2: term
+ Clause 2: term of 12 months
Clause 3: priceA changed item in a list
“pears” has gone and “kiwis” has appeared; “apples” and “plums” are common to both versions.
Input
Original:
apples
pears
plums
Modified:
apples
plums
kiwisResult
apples
- pears
plums
+ kiwisTips and best practices
- To compare content regardless of formatting, first clean both versions with Clean text (extra spaces, empty lines).
- A paragraph written on one long line shows as entirely changed as soon as one word changes: split it into sentences, one per line, to locate the edit.
- To compare lists regardless of order, use Compare two lists instead, which gives the shared items and those unique to each list.
Frequently asked questions
Does the comparator detect changed words within a line?
No. The unit of comparison is the line: a modified line is shown as deleted and then added, and it is up to you to spot the word that changed between the two.
What do the “+” and “-” signs mean?
“-” marks a line found only in the original text, “+” a line found only in the modified text. Common lines start with two spaces.
Do capitals and spaces count?
Yes. The comparison is exact, character by character. Only Windows (CRLF) and Unix (LF) line endings are treated as equivalent.
Can I compare two files?
Yes. Each field accepts a text file import (.txt, .md, .csv and so on). The content is read locally by the browser.
Are my texts sent online?
No. The comparison is calculated in your browser, so you can use it for confidential documents.
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