> For the complete documentation index, see [llms.txt](https://docs.trymito.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.trymito.io/how-to/combining-dataframes/anti-merge-unique.md).
# Anti-merge (unique)
## How to find the difference between datasets
Mito's dataframe difference functionality lets you find unique records across two different dataframes. You can access this functionality on the `Home` tab, by select the `Merge` dropdown and then selecting `Anti Merge`.
Finding unique rows between multiple datasets.
* **Unique in Left:** Includes each row from the first sheet that doesn't have a match in the second sheet.
* **Unique in Right:** Includes each row from the second sheet that doesn't have a match in the first sheet.
Just like the other types of merges, Mito uses the merge key that you select for each sheet to detect matches.
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