Size & Spec Guide
Figures here are guides. If something is sizing-critical — an engagement ring, say — it's worth having it measured properly by a jeweller. Anything you buy can still be returned within 14 days.
Ring sizes
The most reliable way to check at home is to measure a ring that already fits the right finger. Measure the inside diameter across the middle, or wrap a strip of paper around the inside and measure its length for the circumference.
Fingers swell in heat and late in the day, so measure somewhere in between for the truest fit. If you land between two sizes, size up — a slightly loose ring is wearable, a tight one isn't.
| UK size | Inside circumference | Inside diameter |
|---|---|---|
| H | 47.8 mm | 15.2 mm |
| I | 48.7 mm | 15.5 mm |
| J | 49.3 mm | 15.7 mm |
| K | 50.0 mm | 15.9 mm |
| L | 51.2 mm | 16.3 mm |
| M | 52.5 mm | 16.7 mm |
| N | 53.8 mm | 17.1 mm |
| O | 55.1 mm | 17.5 mm |
| P | 56.3 mm | 17.9 mm |
| Q | 57.6 mm | 18.3 mm |
| R | 58.9 mm | 18.8 mm |
| S | 60.2 mm | 19.2 mm |
| T | 61.4 mm | 19.6 mm |
| U | 62.7 mm | 20.0 mm |
| V | 64.0 mm | 20.4 mm |
| W | 65.3 mm | 20.8 mm |
| X | 66.6 mm | 21.2 mm |
| Y | 67.8 mm | 21.6 mm |
| Z | 69.1 mm | 22.0 mm |
Chain & necklace lengths
Length is measured end to end including the clasp. Where a piece has a pendant, it will sit slightly lower than the figures below.
| Length | Approx. | Where it sits |
|---|---|---|
| 40 cm | 16" | Close around the base of the neck — choker length |
| 45 cm | 18" | Just below the collarbone — the most common length |
| 50 cm | 20" | A little below the collarbone |
| 60 cm | 24" | Mid-chest, sits over a top or jumper |
| 75 cm | 30" | Long — worn layered or doubled |
Watch case sizes
Case size is the diameter of the watch face, excluding the crown. It's largely a matter of proportion and preference rather than a strict rule:
- 34–38 mm — smaller, more classic proportions
- 38–42 mm — the most common range, suits most wrists
- 42–46 mm — larger, more prominent on the wrist
As a rough check, the case shouldn't overhang the flat part of your wrist. Strap length is usually adjustable; if a listing gives a wrist-size range, that's the range the fitted strap covers.
Water resistance
The depth on a watch is a pressure rating from static testing, not a diving depth — movement in water creates far more pressure than the number suggests, so it's sensible to treat these conservatively.
| Rating | Suitable for |
|---|---|
| 3 ATM / 30 m | Splashes and rain only. Fine for handwashing, but take it off before swimming or showering. |
| 5 ATM / 50 m | Showering and shallow swimming. Not for diving or high-impact water sports. |
| 10 ATM / 100 m | Swimming and snorkelling. |
| 20 ATM / 200 m | Scuba diving and high-impact water sports. |
Water resistance isn't permanent — seals age. Avoid pressing buttons or adjusting the crown underwater, and rinse with fresh water after swimming in salt water or a chlorinated pool.
Still not sure?
Send us a message with the piece you're looking at and we'll help you work it out.