---
tag: 0TH78S7GBZ
kind: concept
name: Arc length
msc: [26A42, 53A04]
sources:
  - url: https://en.wikipedia.org/wiki/Arc_length
    locator: lead section
same_as:
  wikidata: Q670036
  wikipedia: Arc length
---

## Summary

The arc length of a curve is its length, measured along the curve. It is the supremum of the lengths of inscribed polygonal paths, and an integral of the speed for smooth curves. The node [[arc length|0X7G61297X]] gives the precise definition.