A circumference of 6 cm (60 mm) corresponds to about a US ring size 7 , which is roughly a UK size N.

Quick answer: what ring size is 6 cm?

If by “6 cm” you mean the circumference of your finger (measured around with a tape/string), then:

  • 5.0 cm → US 5, UK J
  • 5.5 cm → US 6, UK L
  • 6.0 cm → US 7, UK N ✅

So the closest standard size for 6 cm is US 7.

How to double‑check at home

To be sure you’ve got the right size, you can quickly re‑measure:

  1. Wrap a strip of paper or string around the finger where you’ll wear the ring, over the knuckle.
  2. Mark where it overlaps, then measure the length in millimeters.
  3. Compare the number with a ring size chart that shows circumference vs US/UK sizes; 60 mm will line up with US 7.

If your measurement is slightly under or over 6 cm (for example 59 mm or 61 mm), you might be between sizes and may want to size up for comfort.

A quick example

Imagine you measure and get exactly 60 mm around your finger. You look at a circumference‑based chart that lists “6 cm – US 7 – UK N,” so you’d confidently order a US 7 ring for that finger.

Do you know if your 6 cm is the finger circumference, or are you measuring the inside diameter of an existing ring (edge‑to‑edge straight across)?