Guides
Ring size guide: measure once, order with confidence
Quick answer
Ring size guide — measure before you fall in love
Ring size is the least glamorous step and the one that prevents the most avoidable pain. A diamond chosen through the 4Cs still fails day one if the band will not pass the knuckle — or spins enough to catch every door handle.
This guide is method. The live Amada size chart is the reference table. Use both.
We build in Hatton Garden. Wrong size late in MTO burns calendar, not just money. Lock size early.
How to measure
- Time it right. End of day. Normal temperature. Not after a long flight or heavy salt meal if you can help it.
- Measure more than once. Two or three readings across a couple of days. Fingers fluctuate.
- Account for the knuckle. Must pass the knuckle, then sit at the base without cutting circulation.
- Match band width. Slim fashion rings and wide engagement mounts do not feel identical at the same stamped size.
- Confirm before production. MTO: locking size early protects your 2–3 week workshop window.
Surprise proposal? Borrow a ring from the correct finger — same hand — and have a jeweller measure the inner diameter. Novelty plastic sizers are not final fine-jewellery gospel.
What to do when measurements fight you
| Situation | Tendency | Action |
|---|---|---|
| Cold hands when measuring | Reads small | Re-measure warm; do not order yet |
| Large knuckle, slim base | Conflict | Prioritise knuckle pass; discuss fit options |
| Moving to a much wider band | Feels tighter | Ask about half-size up |
| Ready-to-ship deadline | Stock sizes only | Filter ready to ship; confirm chart |
| Made-to-order | Size set in production | Confirm before workshop starts |
Ready-to-ship vs made-to-order sizing
Path changes the risk. Full wedge: ready-to-ship vs made-to-order.
- Ready to ship — stocked size that matches the chart. Speed is the point.
- Made to order — most Amada MTO about 2–3 weeks. Wrong size late costs calendar.
Methods that work — and methods that lie
Jeweller measurement with calibrated rings or a mandrel wins when you can visit Hatton Garden or a trusted bench. Borrow-and-measure works when the borrowed ring fits the correct finger and a professional reads inner diameter. Printable chart can start you — follow scale exactly, then confirm before production.
String-and-ruler hacks fail often: string compresses, knots slip, wrong chart systems. UK, US, European sizes do not share casual arithmetic. Stay inside the Amada size chart.
Fingers change — plan for it
Temperature, salt, exercise, pregnancy, weight change alter fit. Perfect in winter can bite in August. Comfort-fit vs flat inner bands feel different at the same stamped size. Major life change coming? Talk temporary strategies — do not guess a future size.
Dominant and non-dominant hands can differ. Always measure the finger that will wear the ring.
Surprise proposals without size disasters
- Borrow a ring from the correct finger; measure discreetly.
- Ask someone who already knows the size.
- Ready size close to estimate with a clear resize plan before purchase.
- Temporary band then final ring after — only if that story fits your relationship, not as a default escape hatch.
Read return and resize notes on the refund policy. Bespoke and altered pieces often sit outside the easy stock path.
International size systems
UK letters, US numbers, European circumference — same finger, bad conversions. Partner lived abroad or bought fashion rings overseas? Do not trust a remembered foreign stamp. Bring the physical ring or a precise inner-diameter reading.
When to re-measure
Re-measure if seasons swing hard between order and proposal, if swelling-related medication changes, or if you jump from thin fashion band to wide engagement mount. Long-haul flight before a same-day fitting? Re-measure if you can.
Two readings disagree by more than a half size? Stop averaging on a napkin. Book a quick check with us or bring the borrowed ring in. Guessing the midpoint is how daytime comfort becomes nighttime tightness.
Common mistakes
- Guessing from “I think I’m a…” texts.
- Measuring once on a cold morning.
- Ignoring width when upgrading from a skinny band.
- Assuming every metal resizes the same with zero risk to settings — ask for the design.
- Skipping our chart for random internet tables that mix US and UK.
How Amada approaches fit
Hatton Garden manufacture and finish. Third-generation. Twenty years online. Trade stock means correct sizes exist more often. London-hallmarked metal. Certified diamonds when listed with IGI/GIA.
Start with the size chart, browse engagement rings, book for a finger measured at 34 Greville Street or on video. Workshop-family reading: BuyFineDiamonds blog.
Metal changes feel — gold vs platinum. Full order: engagement ring buying guide.
Policies
Summaries only. Full terms on the linked pages. Nothing here extends rights beyond applicable UK consumer law. Returns and resizing limits depend on the piece — especially bespoke or altered.