# Set Variable Value is Not Working

The set variable “***input value***” feature does not support math operation. Let's say the user need to calculate "number + 1",

![](https://2.donedone.com/files/by-embedded-asset-guid/379453/2fe3744d-ad96-43b0-a4e6-d97de64835c4/embedded-asset.png)

So if the user wants to perform a calculation of “***number +1***” the correct feature to use is “***math: add (+)***”. Please refer to the image below;

![
](https://2.donedone.com/files/by-embedded-asset-guid/379454/d1e40024-a252-4065-8a8d-d82613675de1/embedded-asset.png)

Also, if you want to perform a higher number of calculations then we would suggest to use “***JavaScript Function***”.

![](https://2.donedone.com/files/by-embedded-asset-guid/379456/a157d395-84f8-4006-8d03-cf8aeab12b60/embedded-asset.png)

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