# Extract number part of a JSON string

**URL:** <https://discourse.nodered.org/t/extract-number-part-of-a-json-string/98981>\
**Category:** General\
**Created:** [7 September 2025 17:54 UTC](https://discourse.nodered.org/t/extract-number-part-of-a-json-string/98981 "2025-09-07T17:54:32Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![racymole](https://avatars.discourse-cdn.com/v4/letter/r/e19b73/32.png) [@racymole](https://discourse.nodered.org/u/racymole)\
**Post date:** [7 September 2025 17:54 UTC](https://discourse.nodered.org/t/extract-number-part-of-a-json-string/98981/1 "2025-09-07T17:54:32Z")

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I am trying to extract the number part of a JSON string to send in a http request, when I just have a number going into my http request I use {{{payload}}} which works fine, with the JSON string, I can feed this into a debug node with the output as msg.payload.combined\_charge\_current and it outputs the value of this as a number into the debug window, all I want is this same number that is output from my debug window to feed into a http request node, I have tried various things such as {{{payload.combined\_charge\_current}}} with various combinations of brackets all which fail and tried to go through a change node which also fails!  
I am guessing that this should be very easy but I can’t seem to find out how!  
I am very new to NODE RED so be gentle 🙂

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**Author:** ![racymole](https://avatars.discourse-cdn.com/v4/letter/r/e19b73/32.png) [@racymole](https://discourse.nodered.org/u/racymole)\
**Post date:** [7 September 2025 18:31 UTC](https://discourse.nodered.org/t/extract-number-part-of-a-json-string/98981/2 "2025-09-07T18:31:53Z")

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I did sort this out (finally) using the “change” node and as expected, it was quite simple in the end!

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**Author:** ![Steve-Mcl](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/steve-mcl/32/4826_2.png) [@Steve-Mcl](https://discourse.nodered.org/u/Steve-Mcl)\
**Post date:** [7 September 2025 19:34 UTC](https://discourse.nodered.org/t/extract-number-part-of-a-json-string/98981/3 "2025-09-07T19:34:14Z")

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Hi, welcome to the forum.

Glad you got sorted in the end.

> [@racymole](#):
>
> I am very new to NODE RED so be gentle

There are a ton of great tips that will help you massively in the this playlist: [Node-RED Essentials](https://www.youtube.com/playlist?list=PLyNBB9VCLmo1hyO-4fIZ08gqFcXBkHy-6). The videos are done by the developers of node-red. They're nice & short and to the point. You will understand a whole lot more in about 1 hour. A small investment for a lot of gain.

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**Author:** ![racymole](https://avatars.discourse-cdn.com/v4/letter/r/e19b73/32.png) [@racymole](https://discourse.nodered.org/u/racymole)\
**Post date:** [7 September 2025 20:28 UTC](https://discourse.nodered.org/t/extract-number-part-of-a-json-string/98981/4 "2025-09-07T20:28:23Z")

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Thanks 🙂

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**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\
**Post date:** [6 December 2025 20:29 UTC](https://discourse.nodered.org/t/extract-number-part-of-a-json-string/98981/5 "2025-12-06T20:29:23Z")

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