# Measuring Pitch on Flat Flex Ribbon jumper cables

**URL:** <https://forum.digikey.com/t/measuring-pitch-on-flat-flex-ribbon-jumper-cables/5299>\
**Category:** Cable Assemblies\
**Tags:** flat-flex-ribbon-jumpers-cables, tech-tips\
**Created:** [January 17, 2020, 8:51pm UTC](https://forum.digikey.com/t/measuring-pitch-on-flat-flex-ribbon-jumper-cables/5299 "2020-01-17T20:51:37Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Paul\_Burmeister](https://avatars.discourse-cdn.com/v4/letter/p/e480ec/32.png) [@Paul\_Burmeister](https://forum.digikey.com/u/Paul_Burmeister)\
**Post date:** [January 17, 2020, 8:51pm UTC](https://forum.digikey.com/t/measuring-pitch-on-flat-flex-ribbon-jumper-cables/5299/1 "2020-01-17T20:51:37Z")

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Here is a little information on looking at the Flat Flex cable jumpers and figuring the Pitch of the Cable.

DigiKey does carry the Flat Flex cable jumpers. Here are the [Jumper cable options](https://www.digikey.com/en/products/filter/flat-flex-ribbon-jumpers-cables/457).

If you are looking to replace a cable or find one to fit a [FFC/FPC connector](https://www.digikey.com/products/en/connectors-interconnects/ffc-fpc-flat-flexible-connectors/399?k=connector+FFc&k=&pkeyword=connector+FFc&sv=0&pv1989=0&sf=0&FV=-8%7C399&quantity=&ColumnSort=0&page=1&stock=1&pageSize=25) the Pitch requirement will be important. The Pitch will be the center to center spacing of the conductors on the cable.

 ![image](https://global.discourse-cdn.com/digikey/original/2X/0/090dfb0699416def913edc6d23756859d8d82ebb.png)

The formula used is **Cable Width = (# of conductors + 1)(Pitch)**  
The + 1 is referring to the ends of the cable. Even though there is not a conductor path there the distance has to be taken into account.

Usually the pitch of the cable is not known. It can be a hard measurement to get.

It will be easier to measure the Full width of the cable and then divide by the (# of contacts + 1)

We will adjust it to **Cable Width / (# of conductors + 1) = Pitch.**  
For example - Cable width 5mm, number of contacts 9.  
Take the 5mm and divide by the number of contacts (9 +1) this will equal .5mm. The .5mm is now the pitch of the cable.