This Kicad PCB Editor python plugin measures the selected track segments lengths and gives the total length in mm. It also estimates resistance for 1 Oz copper and T = 25C.
This guide was used: https://dev-docs.kicad.org/en/python/pcbnew/
This Youtube view was my inspiration: https://www.youtube.com/watch?v=WjDrvnIFPVY
This on-line resistance calculation tool was used to ensure the plugin's results are accurate:
https://www.allaboutcircuits.com/tools/trace-resistance-calculator/