CSV compare


This tool allows to compare CSV files and visualize the differences. It compares line by line, and indicates which fields are different. It is Open source :), you can download the source code here.

You can see the user guide to help you to use this csv compare tool.

First CSV to compare

Second CSV to compare

CSV format settings

User guide

This tool allows to compare two CSV files, and visualize the diff.

Copy and paste, drag and drop your CSV files or directly type in the editors above.
You can also click on "load CSV from URL" button to load your file from a URL (Must be https).
You can also click on "Browse CSV file" button to load your CSV from a local file.

Click on "CSV format settings" to display the settings. You can select the separator, the quote and the escape characters to use for CSV files:

  • Separator: The character that separates columns within each line.
  • Quote: The quoting character to use when a data value is quoted.
  • Escape: The character to use to escape a "quote" character.

Click on "Compare" button to compare your CSV files!

You can choose to display only the rows with differences or to display them all (With a color code to visualize the differences).

You can also directly compare two CSV files by specifying their urls in the GET parameters url1 and url2.
Example: https://extendsclass.com/csv-diff.html?url1=https://extendsclass.com/mock/rest/3b3aea6de65f5bd7576a1079bf9b6ec5/sample1.csv&url2=https://extendsclass.com/mock/rest/3b3aea6de65f5bd7576a1079bf9b6ec5/sample2.csv

This tool highlights in red color the data which are different.

Why compare CSV files ?

Comma-separated values (CSV) is a delimited text file that uses a comma to separate values. Each line of the file is a record which contains fields, separated by commas. Sometimes the separator can be another character (semicolon, tab ...).

Many applications use the CSV format to transfer data. This format is convenient for exporting and / or importing data. For example, databases can often export in this format. It is often preferred for large amounts of data.

Sometimes it is necessary to compare CSV files. For example to detect the differences between two exported files.

It can be complicated when the CSV file are large, this tool allows you to compare CSV easily.

Online CSV compare tool

CSV diff tool allow to compare two CSV files online. The comparison is done directly in your browser, Your CSV files are not sent to the server side! There is no limitation of size or number of rows (But for large files, your browser may not support the processing load and may not return control...).

CSV diff tool makes a line by line comparison, then it compares each field according to their position in the line. Your csv files must be sorted so you can compare them. We do not yet have a tool to sort your CSV, but it is being considered.

It is a new tool, you can give us your feedback, and make comments.

Load CSV From URL
You can report a bug or give feedback by adding a comment (below) or by clicking "Contact me" link (at the top right hand corner of the page).


jole-2019-09-01 09:43
Excellent tool, thank you! I have two easy ways in which it can be greatly improved: Properly parse CSV where the data is quoted, taking into account columns that contain commas in their values. Any kind of "save" or "export", in any format that's easiest to export, as I'd like to view the data somewhere other than this page. Cheers!

Cyril (admin)-2019-11-20 21:12
Thank you :) Thank you for these ideas, I will study this! Regards,

Cyril (admin)-2019-11-29 21:35
Hi, your suggestions have just been put in place :)

Amit-2019-11-20 07:43
Best online CSV comparator tool, I loved it!! The UI show the difference is awesone, data arranged in different columns and i get to know the exact value from two files in one plac, if it is not matching. Thanks

Cyril (admin)-2019-11-20 21:00
Thanks :) !

Ioannis Karagiorgos-2020-01-09 15:44
Great tool, thank you very very much :-)

Jay Bhattachan-2020-02-13 00:52
Great tool, thanks!How about highlighting the row when diff is found? The cell highlight works for files with couple of fields but it is hard to navigate to horizontally if you have more than few columns. I hope this makes sense.

Cyril (admin)-2020-03-27 15:23
Thank you, it is interesting!

ashish sanghvi-2020-03-12 03:49
why exported difference does not show in different color?

Cyril (admin)-2020-03-27 15:22
Hi, the data exported to clipboard is not rich text :(

Nate-2020-03-27 14:10
Tool looks great!
I don't see a privacy page here - what's your data retention policy (i.e when scanning CSV files what data is kept)

Cyril (admin)-2020-03-27 15:26
Hello thank you :)
The CSV files are compared in your browser, they are not sent to the server side, we do not keep anything!
We keep information only for sharing and backups (not available for this tool).

Paresh Bagmar-2020-04-27 20:57
My file is 50MB. when the file is loaded it gets memory error.

Charles-2020-06-02 00:07
Great tool! One feature request/idea:

I compared a large CSV and had trouble finding the differences. It would be nice if it was possible to make the table cells smaller, and/or there was a mark on table rows/columns that had differences in them.

thanks for building a great tool!

Cyril (Admin)-2020-08-16 10:25
Hi, now you can download only the diff

Avinash Kumar-2020-06-03 01:01
Great tool!!,
one feedback - a top level flag/boolean stating if the CSVs are identical or not.

Cyril (Admin)-2020-08-16 10:27
Hi, now you can just show the diff, so it's easy to know if two files are identical or not.

Ancy-2020-06-11 21:48
Great tool, the differences are highlighted online. Suggestion - Once, download is clicked, the highlight is removed. For smaller files its ok but for larger files finding the difference after downloading would be hard.

Cyril (Admin)-2020-08-16 10:25
Hi, now you can download only the diff (with the original row number)

Tim Collett-2020-08-14 01:34
When downloading - can you have an option to download the differences only (with original row number)
I compared an 8868 row csv file and it's hard to spot the red.

Cyril (Admin)-2020-08-15 22:21
Hi, I added the feature :)

Karan Kansal-2020-08-24 23:16

Stephanie Diao-2020-08-26 01:25

Juan Carlos Estrada Nieto-2020-08-27 18:09
I liked this tool a lot. I helped me to compare some files. I only can suggest that the cvs format selects should be one per each file. Because sometimes you get the cvs from different sources, therefore you can control one of them, but you can't control the other. Thanks a lot again :)

Cyril (Admin)-2020-09-15 12:55
Sounds interesting, I take note. Thanks

Frances-2020-09-01 15:39
Can anyone tell me how many rows / column this tool can handle - looking at 35k records and potentially 30 fields per record

Cyril (Admin)-2020-09-15 12:56
The limitation mainly depends on the browser.

Eric-2020-09-15 12:38
Thank you for this exelent tool! It would be a great addition to exclude some columns (e.g. per index number).

Cyril (Admin)-2020-09-15 12:58
Hi, thanks! That sounds interesting.

Nitin Sharma-2020-09-18 11:11
Just one suggestion, Better to show actual header names from CSV files, then showing Field1, Field2...

Mia-2022-03-02 19:37
+1 for this suggestion.

C Gibson-2020-10-12 17:33
I've been using this tool for months and suddenly a few days ago it stopped working when the compare button is selected. No results are shown.

Cyril (Admin)-2020-10-12 21:35
Hello, can you give me more informations ? (Browser version, error messages in console, xml data).
Thank you!

C Gibson-2020-10-14 19:57
Chrome Version 86.0.4240.75
No error messages received - nothing happens when I select the Compare button.

Cyril (Admin)-2020-10-15 17:16
Thanks. I do not reproduce. Did you do a control + F5 to reload the page?

VS-2021-10-11 20:58
Great tool. Is there a file size limit. I am trying to compare 536 KB files.

Ilias-2021-11-08 14:19
Could you add functionality to parse files with a different delimiter than comma?

Cyril (admin)-2021-11-26 20:23
It is already possible, you must click on "CSV format settings" to show options

steve-2021-12-14 04:50
Sadly this tool cannot handle multiline/multirow data (i.e. data with newline characters in), it seems.

Otherwise it'd be great.