How to Find Your Press-On Nail Size (With Size Chart)

By Evera, Founder of BloomOctober 16, 2026

Lovie Bug medium almond press-on nails by Bloom Nails, worn and shown in the box with all ten sizes

Quick answer

Measure: the widest part of each nail, sidewall to sidewall, in millimeters
Match: your numbers to the chart. Thumb sizes are XS 14 mm, S 15 mm, M 16 mm, L 17 mm
Between sizes? Size up and gently file the sides
Fingers in different sizes? Choose the size that fits most of them

Before you fall for a design, take two minutes to check your size. The right fit is the single biggest reason a press-on set looks seamless and lasts: it covers your natural nail without sitting on your skin, rests flat and holds for weeks. Grab a ruler and a strip of tape and we’ll walk you through it.

Why the right size matters

Too big: the press-on overlaps your skin, catches at the edges and lifts within days.
Too small: the sides of your natural nail show or it feels tight, and the gap lets water get under the edge.
Just right: it covers your nail from sidewall to sidewall, rests comfortably and looks like a salon manicure.

How to measure your nails

All you need is a strip of paper or tape, a fine pen and a ruler with millimeters. Measure bare natural nails, so an existing manicure doesn’t add width.

Place paper or tape. Lay a thin strip across the widest part of your natural nail, following its curve from one sidewall to the other. Keep it snug without stretching it.
Mark both sides. Use a fine pen to mark where each sidewall of your nail meets the strip.
Measure in millimeters. Lay the strip flat against a ruler and read the width between your marks.
Repeat for each finger. Measure your thumb, index, middle, ring and pinky, and write each one down. If your hands look different, measure both.

Bloom Nails size guide: measure your nails and choose the right size, XS to L

Bloom size chart (nail width in mm)

Every Bloom set comes in four sizes. Compare every finger with the chart (your thumb alone isn’t enough), then choose the row that fits most of your fingers. Sizes vary between brands, so always use the chart for the set you’re buying.

Size	Thumb	Index	Middle	Ring	Pinky
XS	14	10	11	10	8
S	15	11	12	11	9
M	16	12	13	12	10
L	17	13	14	13	11

Want to see it all on one page? Our size guide has the full chart and measuring steps.

Tips for a perfect fit

Choose the size that fits most of your fingers. It’s normal for one or two fingers to fall in a different size.
Size up if you’re between sizes or have flatter nail beds. You can always file a nail smaller, but you can’t make one bigger.
File the sides, not the base. If a nail is slightly too wide, gently file along its sides until it sits inside your sidewalls. File a little at a time and check again.
Test before you glue. Lay out every nail and check the fit on each finger before you open the adhesive.

How to tell if a press-on fits

Hold the press-on against your natural nail before applying. It should:

Cover your nail from one sidewall to the other
Sit just inside the skin, never on it
Rest comfortably without rocking, pinching or needing force

Once it fits, follow our guide on how to make press-on nails last up to 3 weeks for prep, adhesive and aftercare tips.

Still unsure? Try it in person

Visit Bloom Nails at Westfield Valley Fair in San Jose or Westfield Century City in Los Angeles. Our team can help you compare sizes and see every design up close. See our store locations and hours. Need something outside our four sizes? We make custom nails too.

Press-on sizing questions

How do I know my press-on nail size?

Measure the widest part of each bare natural nail from sidewall to sidewall in millimeters, following its curve, then match your numbers to the size chart. Bloom sets come in XS (14 mm thumb), S (15 mm), M (16 mm) and L (17 mm).

What if I’m between two press-on sizes?

Size up, then gently file the sides of any nail that feels too wide. A slightly larger nail can be filed to fit; a nail that’s too small leaves gaps that let water in.

What if my fingers are different sizes?

That’s completely normal. Choose the size that fits most of your fingers, and file the sides of any nail that’s a little too wide.

How should a press-on nail fit?

It should cover your natural nail from sidewall to sidewall without resting on the skin around it, and feel comfortable without pinching, rocking or needing force. A good fit sits flat and lasts longer.

Can I get custom-size press-on nails?

Yes. Bloom offers custom sizes and designs. Share your measurements on our custom nails page or email hello@bloomnailsco.com.

What if my Bloom set doesn’t fit?

We offer free exchanges on unopened, unused sets in their original packaging within 30 days of delivery, and we cover return shipping within the U.S. Check the fit before applying adhesive, then email hello@bloomnailsco.com with your order number and the size you need. Read the exchange policy.