Ring Size Guide
Knowing how to measure ring size at home saves returns and disappointment. There are three reliable methods, but most guides skip the detail that causes the most wrong sizes: your fingers change size through the day and with temperature. This ring size guide ranks the methods by accuracy, gives you a US size chart and a printable sizer, and explains when to measure.
Key Takeaways
- Measuring a ring that already fits is the most accurate home method.
- Fingers are larger in the evening and in warm weather, and smaller in the cold.
- Measure at the end of the day, at room temperature, more than once.
- Wide bands fit tighter, so go up half a size for bands over about 6 mm.
- How to measure ring size at home well means checking the knuckle as well as the base.
Three Methods Ranked by Accuracy
Here's how to measure ring size at home, from the most to the least reliable method.
| Rank | Method | Accuracy | Watch out for |
|---|---|---|---|
| 1 | Measure a ring that fits | Most accurate | Needs a ring that already fits the same finger |
| 2 | Printable ring sizer | Good | Must print at exactly 100% scale |
| 3 | String or paper strip | Least accurate | Stretch and thickness can throw it off by a size |
Method 1: Measure a ring that fits
Take a ring that fits the same finger comfortably. Measure the inside diameter, edge to edge across the widest point, in millimetres, and find it on the chart below. Or place it on the printable sizer and see which circle matches its inside edge. This is the most accurate way to learn how to measure ring size at home.
Method 2: Use a printable ring sizer
Print the sizer below at 100% scale, with no "fit to page" option, and check that the calibration line measures exactly 50 mm with a ruler. If it doesn't, your printer has rescaled it and the sizes will be wrong. Done properly, it's the next best answer to how to measure ring size at home.
Method 3: String or paper strip
- Cut a thin strip of paper or use non-stretch string.
- Wrap it snugly around the base of the finger, not tight.
- Mark where it overlaps with a fine pen.
- Measure the length in millimetres: that's the circumference.
- Match it to the circumference column in the chart.
This is the least accurate way to measure ring size at home, because string can stretch or dig in. Repeat it three times and use the average.
US Ring Size Chart
Use this chart with any method for how to measure ring size at home. Half sizes sit roughly halfway between the rows.
| US size | Inside diameter | Inside circumference |
|---|---|---|
| 4 | 14.9 mm | 46.8 mm |
| 5 | 15.7 mm | 49.3 mm |
| 6 | 16.5 mm | 51.9 mm |
| 7 | 17.3 mm | 54.4 mm |
| 8 | 18.1 mm | 57.0 mm |
| 9 | 18.9 mm | 59.5 mm |
| 10 | 19.8 mm | 62.1 mm |
| 11 | 20.6 mm | 64.6 mm |
| 12 | 21.4 mm | 67.2 mm |
| 13 | 22.2 mm | 69.7 mm |
The Detail Most Guides Skip: When to Measure
Your finger isn't a fixed size. It swells and shrinks through the day, and this is the most common reason a ring that fit in the shop feels wrong at home. Timing is the missing piece in how to measure ring size at home.
What makes fingers bigger
- Warm weather and hot showers
- The end of the day, after hours on your feet
- Exercise
- Salty meals and alcohol
- Pregnancy and some medical conditions
What makes fingers smaller
- Cold weather and cold hands
- Early mornings
The best time to measure
Measure in the late afternoon or evening, at a comfortable room temperature, when your hands are neither cold nor swollen. Measure on two or three different days and go with the most consistent result. This one habit fixes most errors in how to measure ring size at home.
Tips for an Accurate Fit
- Check the knuckle: the ring must slide over it. If your knuckle is much wider than the base, size for the knuckle.
- Mind the band width: wide bands fit more snugly, so go up half a size.
- Measure the right finger: your dominant hand is often slightly larger.
- Between sizes? Choose the larger size; it's easier to live with a slightly loose ring than a tight one.
These details make how to measure ring size at home far more reliable.
Common Mistakes
- Measuring first thing in the morning or with cold hands.
- Pulling string tight, or using stretchy thread.
- Printing the sizer with "fit to page" turned on.
- Measuring the wrong finger or the other hand.
- Forgetting that wide bands need a larger size.
Avoid these and how to measure ring size at home becomes genuinely reliable.
Sizing a Ring as a Gift
Borrow a ring the person already wears on the same finger and measure it with Method 1. If you can't, an adjustable ring is the safest gift. It's the gift-giver's version of how to measure ring size at home.
Adjustable Rings: Flexible, With Limits
Adjustable rings open slightly to fit a range of sizes, which makes them forgiving if you're unsure of your size. Adjust them gently, a little at a time, and only occasionally: bending metal repeatedly can weaken it or crack any plating. Even with adjustable styles, knowing how to measure ring size at home tells you whether the size range suits you.
Rings From Global Swanky
Use this guide on how to measure ring size at home before you order. Browse more in the Global Swanky jewelry collection.
1. S925 Silver Adjustable Ring with Red Zircon
The S925 Silver Adjustable Ring with Red Zircon is $27.85, with an open, adjustable band in sterling silver.
2. Adjustable Cat Couple Matching Rings
The Adjustable Cat Couple Matching Rings are $20.31, adjustable and ideal as a gift when you're unsure of sizes.
For keeping rings bright, see our guide on how to clean jewelry at home.
Frequently Asked Questions
Is there a simple ring size chart?
Yes. The US chart above lists each size with its inside diameter and inside circumference in millimetres. For example, a US size 7 has an inside diameter of about 17.3 mm and a circumference of about 54.4 mm.
How to measure ring size with string?
Wrap a thin, non-stretch string or paper strip snugly around the base of your finger, mark where it overlaps, and measure the length in millimetres. Match that circumference to the chart. Make sure it can slide over your knuckle, and repeat a few times.
How do I use a ring sizer printable?
Print it at 100% scale, with no fit-to-page option, and check the calibration line with a ruler. Then place a ring that fits on the circles; the circle matching its inside edge is your size.
What is the average ring size?
Commonly quoted averages are around US 6 to 7 for women and US 9 to 10 for men, but fingers vary widely. Always measure rather than guess.
How to size a ring without a sizer?
Measure the inside diameter of a ring that already fits the same finger, or use the string or paper strip method and the chart above. For gifts, borrow a ring the person wears on the right finger.