# \[Solved\] Need help with math conversion
**URL:** https://discourse.nodered.org/t/solved-need-help-with-math-conversion/45661
**Category:** General
**Created:** [14 May 2021 18:59 UTC](https://discourse.nodered.org/t/solved-need-help-with-math-conversion/45661 "2021-05-14T18:59:50Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@007bond](https://discourse.nodered.org/u/007bond)
#### Post date: [14 May 2021 18:59 UTC](https://discourse.nodered.org/t/solved-need-help-with-math-conversion/45661/1 "2021-05-14T18:59:51Z")
Sorry for the silly newbie questions.
OK so I am getting milliamps and I want amps displayed on my dashboard.
So I use a function node with this and all works great.
var o = msg.payload
msg.payload = msg.payload / 1000
return msg;
Ok now the issue.
I am also getting in watt hours and I want to display that as kWh on the dashboard.
So the same math should work.
var o = msg.payload
msg.payload = msg.payload / 1000
return msg;
But for some reason it does not work the dashboard still displays watt hours.
I don't understand why the math operation is not working?
Running debug on the mqtt output shows.
5/14/2021, 2:36:04 PM[node: 1eeb439b.969b4c
wallcharger/wh : msg.payload : string[6]
"309794"
Running debug on the function node output shows nothing. This I think is telling me that the dashboard is not updating and it showing cached info and that nothing is flowing thru my function node.
I don't get it.
**OK so I did figure this out and I wanted to post in case someone else has the same issue.**
**I just decided to delete the function node and add it again. Then all of a sudden the debug node had output and popped in the formula and its working.**
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### Author:  [@TotallyInformation](https://discourse.nodered.org/u/TotallyInformation)
#### Post date: [14 May 2021 20:18 UTC](https://discourse.nodered.org/t/solved-need-help-with-math-conversion/45661/2 "2021-05-14T20:18:03Z")
> [@007bond](#):
>
> wallcharger/wh : msg.payload : string[6]
> "309794"
This contains the clue. It is a string and not a number. While JavaScript isn't strongly typed like some languages, even so most Math will only work correctly on an actual number. You can also force a string to a number, there are a couple of different functions that will do that.
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### Author:  [@007bond](https://discourse.nodered.org/u/007bond)
#### Post date: [14 May 2021 22:45 UTC](https://discourse.nodered.org/t/solved-need-help-with-math-conversion/45661/3 "2021-05-14T22:45:59Z")
IC thank you just for my education as I am new could you share in this example how I would go about changing the string to a number. Thanks again.
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### Author:  [@Ranki](https://discourse.nodered.org/u/Ranki)
#### Post date: [14 May 2021 22:56 UTC](https://discourse.nodered.org/t/solved-need-help-with-math-conversion/45661/4 "2021-05-14T22:56:00Z")
> **[Here, Let Me Google That For You](https://googlethatforyou.com/?q=javascript%20string%20to%20number)**
>
> Passive-aggressively teach your friends how to Google. For all those people who find it more convenient to ask you rather than search it themselves. Not associated with Google.
🙃
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### Author:  [@007bond](https://discourse.nodered.org/u/007bond)
#### Post date: [14 May 2021 23:26 UTC](https://discourse.nodered.org/t/solved-need-help-with-math-conversion/45661/5 "2021-05-14T23:26:06Z")
Yea I deserved that one 🤣
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### Author:  [@system](https://discourse.nodered.org/u/system)
#### Post date: [28 May 2021 23:26 UTC](https://discourse.nodered.org/t/solved-need-help-with-math-conversion/45661/6 "2021-05-28T23:26:41Z")
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