How can I auto update a custom field value to the sum of 2 other custom field values?

[Sean_Ohannrachain]

I have a custom field called Story Points, and I also have other custom fields called Dev Points and QA Points. After there are values set on Dev Points and QA Points, I want to automate the summing up of the 2 values and update the Story Points field value. 

I have been looking up old similar questions, but I can't get it to work. I'm not familiar with JSON, I'm in a non-tech role, but I have been trying different variations that were posted b others regardless 

Depending on the variation I have tried, I have received different errors. The current variation I have tried is {
"fields": {
customfield_10005: {{#=}} {{customfield_11893}} + {{customfield_11894}} {{/}}
}
} 

10005 is SP, 11893 is DP and 11894 is QAP. 

Any help here would be greatly appreciated, thanks!

[Trudy Claspill · Accepted solution]

Hello @Sean_Ohannrachain 

Welcome to the Atlassian community!

You should not need to use JSON for this.

You should be able to select your Story Points field as the one you want to Set.

Then enter your formula in the field for setting the value thus:

This should work if all the fields are defined as Number type fields.

[Sean_Ohannrachain]

Thanks a mil Trudy, that worked perfectly. I didn't even realise that I could type in there, complete mistake by me! 

Thanks for the welcome to the community, it's a great help for me!