Ring sizes

To choose the right ring size, the most important thing is to know the ring’s inner diameter or the circumference of your finger. In Lithuania, the size is usually indicated by a number close to the ring’s inner diameter in millimeters. The ring size chart provided will help you compare sizes in mm and cm and choose the closest appropriate option.

In Short

• You can choose a ring size based on the ring’s inner diameter or your finger circumference;
• For example, size 17 corresponds to an inner diameter of approximately 17.1 mm;
• If you know the measurement in centimeters, you can compare it to the table provided;
• Ring size notation differs between Lithuania, the United Kingdom, and the U.S., so it’s important to check size equivalents when shopping abroad.

Ring Size Chart in cm and mm

The table below shows the equivalents between Lithuanian ring sizes and inner diameters. The inner circumference of the finger or ring in centimeters is provided as a rough mathematical estimate.

What does the ring size number mean?

In Lithuania, the ring size number corresponds to the ring’s inner diameter in millimeters. Sizes are usually given in intervals—for example, 16, 16.5, 17, 17.5, and so on. It is important to understand that the size number and the exact diameter do not always match to the nearest tenth of a millimeter. For example:

• Size 16 – approximately 16.1 mm;
• Size 17 – approximately 17.1 mm;
• Size 18 – approximately 18.1 mm;
• Size 19 – approximately 19 mm;
• Size 20 – approximately 20 mm.

Therefore, when choosing a ring, it’s best to refer to a specific size chart rather than just the size number.

How to use the ring size chart?

If you know the ring’s inner diameter

Find the value closest to your measurement in the “Inner Diameter” column. For example:

18.5 mm → size 18.5.

If you know your finger circumference

Find the closest value in the “Approximate Circumference” column. For example:

about 5.37 cm → size 17.

Ring Size Calculator: How Are Circumference and Diameter Related?

A ring’s inner circumference and diameter are directly related. Therefore, knowing one measurement allows you to estimate the other. A simple formula:

inner diameter ≈ circumference ÷ 3.14

For example, if the circumference is 53.7 mm—according to the size chart, this corresponds to approximately size 17:

53.7 ÷ 3.14 ≈ 17.1 mm

This formula can serve as a simple ring size calculator, but it’s best to choose the final size based on the specific retailer’s size chart.

Are ring sizes the same across different countries?

No. One of the most common sources of confusion when buying a ring online is that different countries use different sizing systems. The chart includes three notations:

• Lithuanian size – numerical;
• UK/European notation – usually alphabetic;
• U.S. size – a separate numerical system.

For example, a Lithuanian size 14 in this table corresponds to a UK size F and a US size 3. Therefore, when ordering a ring based on a foreign sizing system, it is recommended to first compare the inner diameter in millimeters—this helps avoid confusion between different notations.

What should you do if you fall between two ring sizes?

If your measurement falls between two sizes in the chart, it’s not always worth rounding off purely based on math. The right choice may also depend on:

• the specific design of the ring;
• the width of the band;
• the desired fit of the ring;
• the finger on which the ring will be worn.

For more details on measurement specifics and choosing wider or narrower rings, read the article “How to measure finger sizes for a ring at home”.

Ring Sizes for Engagement and Wedding Rings

The right size is especially important when choosing jewelry for everyday wear, such as an engagement ring or a wedding ring. Before choosing a specific model, it’s best to determine the size first and then browse through suitable rings.

What should you do if the ring size you chose doesn’t fit?

If a ring you already own is too large or too small, the size of some rings can be professionally adjusted. “Auksinė Svajonė” offers ring resizing services, taking into account the type of metal, the ring’s construction, and any stones set in the ring.

Frequently Asked Questions About Ring Sizes

How do I determine my ring size?

If you already know the ring’s inner diameter or your finger’s circumference, compare the result to the ring size chart. If you don’t know the measurement yet, use our separate guide on how to measure your ring size at home.

What is the ring size if the circumference is about 5.5 cm?

The closest size listed in the chart is 17.5, which has an approximate inner circumference of 5.56 cm.

What does ring size 17 mean?

According to the size chart used, a Lithuanian size 17 corresponds to an inner diameter of approximately 17.1 mm.

Are U.S. and Lithuanian ring sizes the same?

No. The U.S. uses a different sizing scale, so a U.S. size cannot be directly equated to a Lithuanian size. The most reliable method is to compare the inner diameter of the ring and use a conversion chart.

What should you do if the ring is too big or too small?

The possibility of resizing depends on the specific construction of the ring. A professional jeweler can assess whether the ring can be safely enlarged or reduced.

Not sure which size to choose?

If you’re still unsure between several sizes based on the chart, consult with a jeweler. Once you’ve chosen the right size, you can move on to the most important part—selecting the ring you’ll want to wear every day.