At LabGrownBox, we want your ring to feel as perfect as it looks. That starts with the right size. Our ring size guide makes it simple for you to measure your finger at home and shop with confidence.
Whether you are buying for yourself or planning a surprise, knowing the correct size ensures comfort, security, and a flawless fit.

Why Ring Size Matters

The perfect ring should slide on easily yet stay securely in place. A ring that’s too tight can feel uncomfortable, while one that’s too loose may slip off.
Accurate sizing ensures your ring feels natural every day. That’s why LabGrownBox is committed to helping you find your ring size before you buy.

Visual Guide

Measure with an Existing Ring

Use a String or Paper Strip

Use a Printable Ring Sizer

Get Measured at a Jeweler

Method 1: Using a Ring You Already Own

What You'll Need:

A ring that fits the intended finger perfectly
A ruler or measuring tape
A piece of paper
A pen or pencil

Steps:

Place the ring on a piece of paper
Trace the inside of the ring with a pen
Measure the diameter of the circle in millimeters
Use our size chart below to find your ring size

Method 2: Using String or Paper Strip

What You'll Need:

A piece of string or thin strip of paper
A ruler or measuring tape
A pen to mark the string/paper

Steps:

Wrap the string or paper around the base of your finger
Mark where the string/paper overlaps
Measure the length in millimeters
Use our circumference chart below to find your size

Ring Size Chart

US Size	UK Size	Diameter (mm)	Circumference (mm)
3	F	14.1	44.2
3.5	G	14.5	45.5
4	H	14.9	46.8
4.5	I	15.3	48.0
5	J	15.7	49.3
5.5	K	16.1	50.6
6	L	16.5	51.9
6.5	M	16.9	53.1
7	N	17.3	54.4
7.5	O	17.7	55.7
8	P	18.1	57.0
8.5	Q	18.5	58.3
9	R	18.9	59.5
9.5	S	19.4	60.8
10	T	19.8	62.1
10.5	U	20.2	63.4
11	V	20.6	64.6
11.5	W	21.0	65.9
12	X	21.4	67.2

Important Tips for Accurate Measurement

Best Time to Measure

Measure your finger at the end of the day when it's at its largest size. Fingers can swell throughout the day due to temperature and activity.

Temperature Matters

Cold weather can cause fingers to shrink, while warm weather can cause them to expand. Measure at room temperature for best results.

Measure Multiple Times

Take measurements 3-4 times to ensure accuracy. If you get different results, go with the larger size for comfort.

Consider Ring Width

Wider bands (over 6mm) may require a size up from your normal size for comfort.

Knuckle Size

If your knuckle is much larger than the base of your finger, measure both and choose a size in between.

Different Fingers

Each finger may be a different size. Always measure the specific finger where you'll wear the ring.

Printable Ring Sizer

For the most accurate measurement, you can print our ring sizer tool. Make sure to print at 100% scale (no scaling) for accurate measurements.

Print the ring sizer below at 100% scale
Cut out the ring sizer
Insert the pointed end through the slot
Place around your finger and pull until snug
Read the size where the sizer overlaps

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Why Ring Size Matters

Visual Guide

Method 1: Using a Ring You Already Own

What You'll Need:

Steps:

Method 2: Using String or Paper Strip

What You'll Need:

Steps:

Ring Size Chart

Important Tips for Accurate Measurement

Best Time to Measure

Temperature Matters

Measure Multiple Times

Consider Ring Width

Knuckle Size

Different Fingers

Printable Ring Sizer

Still Need Help?

📞Contact Us : +1 (929) 606-7245

📩Email on : support@labgrownbox.com

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