Printable ring sizer
Print this page, check the square with a ruler, then measure. The check square is the part that matters: browsers shrink pages to fit the paper by default, and a sizer printed 4% small reads close to a full size too tight — 0.7 of a size at US 3, 1.1 at US 13. Every printable sizer that skips this step is guessing. Once you have a measurement, see it converted across every system on the ring size chart.
Before you print
- In the print dialog set Scale to 100% — not “Fit to page”, not “Shrink to fit”. This is the single step that decides whether the sheet is accurate.
- Use A4 or US Letter. Either works; the gauge fits both.
- Measure the printed square with a ruler — outside edge to outside edge of the outline, not inside to inside. Every side must be exactly 50 mm. If it is not, your printer scaled the page — fix the scale setting and print again rather than trying to correct for it.
Nothing is uploaded and there is no PDF to download — this is the page itself, printed.
1 · Check the scale first
Measure this square from the outside of the outline to the outside of the outline opposite — not inside to inside, which reads 0.8 mm small. Every side must be exactly 50 mm. If it is not, the sheet is scaled and every size below it will be wrong.
50 mm × 50 mm, outside edge to outside edge
A ruler is enough. If you do not have one, every bank card in the world is the same size under ISO/IEC 7810: 85.60 mm long and 53.98 mm wide. Hold the card’s short edge along one side of the square — the square should fall 3.98 mm short of it.
2 · Measure a ring you already own
Lay a ring over the circles. The right one is the circle whose outline just disappears inside the ring’s inner edge. If the ring sits between two, take the larger.
- US 314.1 mm · UK F½ · EU 44 · JP 4
- US 414.9 mm · UK H½ · EU 47 · JP 7
- US 515.7 mm · UK J½ · EU 49 · JP 9
- US 616.5 mm · UK L½ · EU 52 · JP 12
- US 717.3 mm · UK N½ · EU 54 · JP 14
- US 818.1 mm · UK P½ · EU 57 · JP 16
- US 918.9 mm · UK R½ · EU 60 · JP 19
- US 1019.8 mm · UK T½ · EU 62 · JP 21
- US 1120.6 mm · UK V½ · EU 65 · JP 24
- US 1221.4 mm · UK Y · EU 67 · JP 26
- US 1322.2 mm · UK Z+1 · EU 70 · JP 29
- US 1423.0 mm · UK Z+3 · EU 72 · JP 31
3 · Or measure your finger with the ring size ruler
Cut along the strip. Wrap it around the base of your finger, snug but not tight, and read the millimetre mark where the end meets the strip. That figure is your circumference — find it in the table below.
Ring size ruler: circumference in millimetres, measured from the left end · cut along the outline · US 3 to 15 run from 44 to 75 mm
| Circumference | US | UK | EU | JP | Diameter |
|---|---|---|---|---|---|
| 44.2 mm | 3 | F½ | 44 | 4 | 14.1 mm |
| 46.8 mm | 4 | H½ | 47 | 7 | 14.9 mm |
| 49.3 mm | 5 | J½ | 49 | 9 | 15.7 mm |
| 51.9 mm | 6 | L½ | 52 | 12 | 16.5 mm |
| 54.4 mm | 7 | N½ | 54 | 14 | 17.3 mm |
| 57.0 mm | 8 | P½ | 57 | 16 | 18.1 mm |
| 59.5 mm | 9 | R½ | 60 | 19 | 18.9 mm |
| 62.1 mm | 10 | T½ | 62 | 21 | 19.8 mm |
| 64.6 mm | 11 | V½ | 65 | 24 | 20.6 mm |
| 67.2 mm | 12 | Y | 67 | 26 | 21.4 mm |
| 69.7 mm | 13 | Z+1 | 70 | 29 | 22.2 mm |
| 72.3 mm | 14 | Z+3 | 72 | 31 | 23.0 mm |
| 74.8 mm | 15 | Z+5 | 75 | 33 | 23.8 mm |
UK charts vary by up to half a size, mostly because many list only whole letters. Ours follows the published British rule of 1.25 mm per letter. If you get a half size and your jeweller stocks only whole letters, go up to the next letter — rounding down gives a ring smaller than your finger. Or give them the circumference in millimetres.
Printed from ringsizetool.com · sizes computed from ISO 8653, the 1987 British metric rule and the Japanese 号 scale, not copied from another chart.
Why this is a page, not a PDF
Most printable ring sizers are a PDF download. This one is the page you are reading, printed. That is a deliberate choice, and it is not about saving you a download.
A PDF does not solve the scaling problem. It moves it. Adobe Acrobat’s page-sizing options are Fit, Shrink oversized pages and Actual size, and only the last prints at 100%. Fit scales the page to your printer’s imageable area; Shrink oversized pages scales down anything larger than that area — which a full A4 or Letter page usually is, because desktop printers cannot print to the edge of the sheet. So a PDF reader hands you the same trap as a browser with a different word on the button.
Which means the thing that makes a printed sizer trustworthy is not the file format. It is the check square. A PDF without one is exactly as unreliable as a web page without one. This sheet has one, and measuring it is the first instruction rather than a footnote.
The rest follows from that: nothing to download, no email address to hand over, and it prints from a phone as readily as from a laptop.
If the square does not measure 50 mm
Reprint it. Do not try to correct for the error arithmetically — you would have to apply it to the gauge circles and the finger strip separately, and a mistake there is silent in a way a wrong square is not.
The square is smaller than 50 mm
The page was scaled down, which is the default nearly everywhere. Set the scale to 100%:
- Chrome and Edge — More settings → Scale → Custom → 100
- Firefox — the Scale field in the print preview, set to 100 rather than “Fit to page width”
- Safari — the Scale field, set to 100%
The square is larger than 50 mm
Less common. Usually a scale set above 100 by hand, or a sheet laid out for one paper size printed onto the other with a fit option switched on. Set the scale to 100% and pick the paper size actually in the tray.
The sides do not match each other
One side right and the other wrong is not a scale problem — the paper fed skewed, or the printer is scaling the two axes independently. Reprint, and if it repeats, try the other paper size or another printer. A sheet that is out of square cannot be rescued by measuring more carefully.
Measuring the square itself
Lay the sheet flat on a table rather than holding it up, use the millimetre edge of the ruler, and read outside edge to outside edge of the printed outline. Reading inside-to-inside instead measures 49.2 mm, because the outline is 0.4 mm thick on each side. That is a 1.6% error — about 0.3 of a size — and it is the wrong kind of wrong: it sends you back to reprint a sheet that was already correct.
If your print dialog will not give you 100% at all, use the on-screen sizer instead. It calibrates against a bank card and never involves a printer.
Why this sheet is in whole sizes
The on-screen sizer gives quarter sizes. This sheet does not, and the reason is the ink.
A quarter of a US size is 0.20 mm of inner diameter. The outline of each gauge circle is drawn 0.30 mm thick. The line you would be matching your ring against is wider than the difference it would have to show you, so a quarter-size gauge on paper would be decoration rather than measurement. Half sizes are 0.41 mm — only about a third wider than the stroke — which is why they are not here either.
On screen there is no stroke to fall inside. The circle is drawn at your own calibration and moves a hundredth of a millimetre at a time. That is the honest reason both versions exist, rather than one being a lesser copy of the other.
What accuracy to expect
With the square measuring 50 mm and an unhurried reading, a printed sheet will put you within roughly a third of a size. Two things dominate what is left: how snugly you pull the paper strip, and whether the ring is sitting flat over the circle rather than tilted.
What the check square removes is the largest source of error and the only silent one. A page printed at “fit to page” can easily be 4% small, which is 0.7 of a size at US 3 and 1.1 at US 13 — and nothing on the sheet would look wrong. For a sheet to be a size and a half out it would have to be about 7% small, which is rarer, but the point is that you cannot see either one without measuring the square.
If the reading matters — an engagement ring, or a size you cannot return — measure on a day when your hands are neither cold nor swollen, take it twice, and have a jeweller confirm it on a steel ring stick before you buy.
No printer?
The on-screen sizer calibrates against a bank card instead of a printer, which removes the scaling problem entirely, and it carries quarter sizes that paper cannot resolve.
Measure on screen instead →Printable ring sizer questions
Taken word for word from Google’s “People also ask”. Nothing here is invented to pad the page.
Do printable ring sizers work?
They do, but only if the print came out at true scale — and most do not, because printers default to "fit to page" and shrink everything by a few per cent. A few per cent of a ring is most of a size. That is why our printable page carries a scale-check square you measure with a ruler before you use anything else on the sheet.
Is there a printable ring sizer?
Yes — this page is one, and there is no PDF to download and no email to hand over. Print it, check the square measures the stated width with a ruler, then use the ring-hole gauge or cut out the finger strip.
Can I make my own ring sizer?
Yes. Cut a strip of paper about 1 cm wide and 10 cm long, wrap it round the base of the finger, mark where it overlaps and measure the flat length — that is your inner circumference. A home-made strip is as accurate as a printed one, because the accuracy comes from the ruler, not the paper.
Why is there no PDF to download?
Because a PDF would not make the sheet more accurate, and it would add a step. Adobe Acrobat's page-sizing options are Fit, Shrink oversized pages, and Actual size — only the last prints at 100%, and the first two scale a full A4 or Letter page down because desktop printers cannot print to the edge of the sheet. A PDF reader offers the same trap as a browser with different wording on the button. What makes a printed sizer trustworthy is the check square, not the file format, so this page carries the square and skips the download.
My printed square measures 48 mm instead of 50. Is that close enough?
No — reprint it with the scale set to 100%. That is a 4% error, and because it scales with the size you are measuring it is worth 0.7 of a US size at the small end of the range and 1.1 at the large end — roughly a full size either way. Do not try to subtract it afterwards: the correction lands differently on the gauge circles and the finger strip, and getting it wrong is invisible.
Can I print a ring sizer from my phone?
Yes, and this page is built for it — there is no file to open in another app first. The scale control still matters: in iOS and Android print dialogs it usually sits behind an options or settings expander, and the default is to fit the page. Set it to 100%, print, and measure the square exactly as you would from a laptop. If the phone's dialog gives you no scale control at all, use the on-screen sizer instead.
Does it matter whether I print on A4 or US Letter?
No. The sheet is laid out to fit inside both, so either works as long as the paper in the tray matches the paper size selected in the print dialog. A mismatch is one of the common ways a page gets silently scaled — a sheet set for A4 sent to a Letter tray with a fit option enabled will shrink. The check square catches it.
Is a printed ring sizer as accurate as measuring on screen?
Not quite, and the difference is the ink rather than the paper. Each gauge circle here is outlined at 0.30 mm, while a quarter of a US size is only 0.20 mm of diameter — the printed line is wider than the difference it would have to show, so this sheet carries whole sizes only. On screen the circle is drawn at your own calibration with no stroke to fall inside, which is what makes quarter sizes meaningful there. A correctly printed sheet is still good to about a third of a size, which is enough for most purchases.