How to measure your ring size at home
The most reliable home method is the paper strip: wrap it around your finger, mark the overlap, and measure the length in millimetres — that length is your ring's inside circumference, so 54 mm means about a US 7. If you already own a ring that fits, measuring its inside diameter is even quicker.
Method 1 — The paper strip
- Cut a thin strip of paper about 5 mm wide and 10 cm long (a strip of sticky-note or printer paper is fine). Avoid string or thread — it stretches and reads small.
- Wrap it around the base of the finger you will wear the ring on, snug but not tight. Slide it over the knuckle once to make sure it passes — the ring has to get over the knuckle too.
- Mark where the end overlaps with a fine pen, then lay the strip flat and measure from the end to the mark in millimetres. That is the inside circumference.
- Convert the measurement. Match it to the circumference column of the ring size chart: 51.9 mm ≈ US 6, 54.4 mm ≈ US 7, 57.0 mm ≈ US 8. Between two rows, choose the larger size.
Method 2 — Measure a ring you already own
- Pick a ring that fits the same finger well — not a pinky ring for a ring-finger purchase.
- Measure the inside diameter with a ruler or calipers: the distance across the middle of the ring, inside edge to inside edge, in millimetres.
- Or skip the ruler: use the on-screen sizer — calibrate with a bank card, then rest the ring on the circle and read the size directly.
- Convert: 16.5 mm ≈ US 6, 17.3 mm ≈ US 7, 18.1 mm ≈ US 8, 19.0 mm ≈ US 9. The full mapping is on the chart page.
Mistakes that ruin the measurement
Measuring cold hands. Fingers shrink in the cold and swell in heat; measure in the evening at room temperature for the most generous, safest reading. Pulling the strip tight. The strip should sit like a ring sits — touching all around, not compressing the skin. Measuring once. Take two or three readings across the day and use the largest; finger size can shift by a quarter size between morning and evening. Guessing for a wide band. If the ring will be wider than about 6 mm, add a quarter to a half size to whatever you measured.
Frequently asked questions
How accurate is the paper strip method?
Done carefully, within about a quarter to a half size — plenty for fashion rings and a good starting point for anything expensive, which a jeweller should confirm with a sizing set.
Can I measure someone's size in secret?
Borrow a ring they wear on the same finger and use method 2, or trace its inside circle on paper and measure that. If neither is possible, the averages are the fallback most surprise buyers use.
What if my knuckle is much bigger than the base of my finger?
Measure both places. The ring must pass the knuckle but sit at the base; if the difference is more than a full size, tell the jeweller — slightly oval or hinged shanks exist for exactly this case.