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SIZE GUIDE
Choosing the right size is part of creating a piece of jewelry that you can wear comfortably. At Febril, we use the US ring sizing system, identified as US. If you know your size in another system, you can check the equivalents in this guide.
Before submitting your request, confirm which finger and on which hand you will be wearing the ring. If you have any questions about the sizing, write to me at info.febril@gmail.com and we will review the information before confirming your order.
How to find your size
Measurement at a jewelry store
The most reliable option is to go to a jewelry store to have your finger measured with a ring sizer. Test how the sizer slides on and off: it should pass over the knuckle and sit comfortably at the base of your finger. The size should allow you to wear the ring without it pinching or slipping off easily. Ask them to tell you the size in the US system and its internal diameter in millimeters.
Measuring a ring you already have
If you have a ring that fits you well, you can measure its inside diameter to get a reference for your size. You will need the ring and a ruler with millimeter markings.
Step 1. Choose a ring that you wear comfortably on the same finger and the same hand where you will wear the new piece.
Step 2. Make sure the inside is circular and that the ring is not deformed.
Step 3. Place it on a flat surface and measure the distance in millimeters between its two inside edges, going through the center. Do not include the thickness of the metal: you only need to measure the inside space.
Step 4. Note the measurement in millimeters, keeping any decimals you can read. Do not round up directly to the next millimeter.
Step 5. Find the closest measurement in the “Inside diameter” column of the chart and look up the corresponding US size.
Choosing the right size is part of creating a piece of jewelry that you can wear comfortably. At Febril, we use the US ring sizing system, identified as US. If you know your size in another system, you can check the equivalents in this guide.
Before submitting your request, confirm which finger and on which hand you will be wearing the ring. If you have any questions about the sizing, write to me at info.febril@gmail.com and we will review the information before confirming your order.
How to find your size
Measurement at a jewelry store
The most reliable option is to go to a jewelry store to have your finger measured with a ring sizer. Test how the sizer slides on and off: it should pass over the knuckle and sit comfortably at the base of your finger. The size should allow you to wear the ring without it pinching or slipping off easily. Ask them to tell you the size in the US system and its internal diameter in millimeters.
Measuring a ring you already have
If you have a ring that fits you well, you can measure its inside diameter to get a reference for your size. You will need the ring and a ruler with millimeter markings.
Step 1. Choose a ring that you wear comfortably on the same finger and the same hand where you will wear the new piece.
Step 2. Make sure the inside is circular and that the ring is not deformed.
Step 3. Place it on a flat surface and measure the distance in millimeters between its two inside edges, going through the center. Do not include the thickness of the metal: you only need to measure the inside space.
Step 4. Note the measurement in millimeters, keeping any decimals you can read. Do not round up directly to the next millimeter.
Step 5. Find the closest measurement in the “Inside diameter” column of the chart and look up the corresponding US size.
For example, an inner diameter of approximately 16.5 mm corresponds to a US size 6.
Can I measure my finger with string or paper?
I do not recommend using this measurement as your sole reference to confirm an order. The material can stretch, bend, or be pulled tighter than necessary. Furthermore, measuring only the base of the finger does not ensure that the ring will fit over the knuckle.
If you do not have a reference ring, the best option is to use a ring sizer or visit a jewelry store.
IMPORTANT
Finger size can vary throughout the day and with the temperature. Confirm the measurement under normal conditions and check again if you notice variations.
Do not assume that the same finger is the exact same size on both hands.
If you are between two sizes, send me the measurement you got and the model you are interested in. We will review which option is best before confirming the order.
Size conversion chart
The US size is the reference you should select on the Febril form. The other columns are for your reference if you know your size in another system.
For example, an inner diameter of approximately 16.5 mm corresponds to a US size 6.
Can I measure my finger with string or paper?
I do not recommend using this measurement as your sole reference to confirm an order. The material can stretch, bend, or be pulled tighter than necessary. Furthermore, measuring only the base of the finger does not ensure that the ring will fit over the knuckle.
If you do not have a reference ring, the best option is to use a ring sizer or visit a jewelry store.
IMPORTANT
Finger size can vary throughout the day and with the temperature. Confirm the measurement under normal conditions and check again if you notice variations.
Do not assume that the same finger is the exact same size on both hands.
If you are between two sizes, send me the measurement you got and the model you are interested in. We will review which option is best before confirming the order.
Size conversion chart
The US size is the reference you should select on the Febril form. The other columns are for your reference if you know your size in another system.
| US · Febril | Diámetro interior (mm) | Europea | Reino Unido |
|---|---|---|---|
| 3 | 14,1 | 44 | F |
| 3.5 | 14,5 | 46 | G |
| 4 | 14,9 | 47 | H |
| 4.5 | 15,3 | 48 | I |
| 5 | 15,7 | 49 | J |
| 5.5 | 16,1 | 51 | K |
| 6 | 16,5 | 52 | L |
| 6.5 | 16,9 | 53 | M |
| 7 | 17,3 | 54 | N |
| 7.5 | 17,7 | 56 | O |
| 8 | 18,1 | 57 | P |
| 8.5 | 18,5 | 58 | Q |
| 9 | 19,0 | 60 | R |
| 9.5 | 19,4 | 61 | S |
| 10 | 19,8 | 62 | T |
| 10.5 | 20,2 | 64 | U |
| 11 | 20,6 | 65 | V |
| 11.5 | 21,0 | 66 | W |
| 12 | 21,4 | 67 | X |
Equivalencias aproximadas. Utilizamos el sistema US.
Need help?
If your size does not appear on the form, you need an in-between size, or you have questions about measuring, write to me via my digital channels before submitting your request.
You can share the model you are interested in, the finger and hand where you will wear it, the measurement you obtained, and how you took it. If you already know your size, convert it to the US system used by Febril.
Size adjustments
The possibility of resizing a ring depends on its design. Before ordering, confirm your measurement: not all pieces allow for subsequent modifications. You can check the adjustment terms in our warranty, exchanges, and returns policy.
Need help?
If your size does not appear on the form, you need an in-between size, or you have questions about measuring, write to me via my digital channels before submitting your request.
You can share the model you are interested in, the finger and hand where you will wear it, the measurement you obtained, and how you took it. If you already know your size, convert it to the US system used by Febril.
Size adjustments
The possibility of resizing a ring depends on its design. Before ordering, confirm your measurement: not all pieces allow for subsequent modifications. You can check the adjustment terms in our warranty, exchanges, and returns policy.
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