Measuring a saddle can mean two different things: finding a bicycle saddle width that supports your sit bones, or checking a horse saddle’s seat size for the rider. The methods are not interchangeable, so first identify which saddle you are measuring and what you need to learn. This guide covers both. For a bicycle, you can estimate sit-bone spacing and compare it with a saddle’s stated width. For a horse saddle, you can measure the seat and use the maker’s sizing convention as a starting point. Neither measurement alone guarantees a comfortable fit: bike setup and the fit of a saddle on a horse also matter.
What You’ll Need
- For a bicycle saddle: a tape measure or ruler, a firm flat chair or bench, and corrugated cardboard or a sheet of firm, easily marked material. A helper can make the impressions easier to read.
- For a horse saddle: a flexible tape measure or ruler, good light, and the saddle placed securely on a stable surface. Check the saddle maker’s sizing instructions if available.
- For either type: paper and a pen to record measurements, including the units and the exact points measured.
Step-by-Step
- Decide what you are trying to measure. On a bicycle, people usually need either the rider’s sit-bone spacing, the saddle’s width, or the saddle’s position on the bike. These are different measurements. For a horse saddle, seat size describes the space intended for the rider; it does not tell you whether the saddle’s tree and panels fit the horse. Write down your goal before measuring so you do not compare unlike numbers.
- For a bicycle, measure your sit-bone spacing. Put the cardboard on a firm, level chair or bench. Sit on it in the posture you normally use while riding, with your feet supported and your weight settled evenly. Avoid leaning far forward or reclining, since changing your pelvic angle changes where your sit bones press. Stay still for a few seconds, then stand straight up without sliding across the surface. Look for the two strongest, distinct impressions. If the marks are faint, repeat the process; do not assume that every dent is a sit-bone mark.
- Measure between the centers of the two impressions. Mark the center of each clear impression, then measure the straight-line distance from one center to the other. Record the result in millimetres or centimetres and label it as sit-bone spacing. If the impressions are broad or uneven, take another measurement rather than choosing the outside edges. A bike shop may be able to measure your sit bones with a purpose-made device, which can be easier to interpret than a home impression.
- Use that result as a guide to bicycle saddle width. Look up the saddle’s actual width and the manufacturer’s fit guidance. The saddle should support the sit-bone area without forcing you onto an excessively wide nose or causing rubbing at the inner thighs. There is no single width calculation that works for every rider: posture, flexibility, riding position, saddle shape, and the maker’s design all affect the choice. Treat your measurement as a useful starting point, not a guarantee. If possible, try the saddle or ask a bike fitter or shop to help compare options.
- Measure a bicycle saddle itself, if that is your goal. Remove it from the bike if doing so makes the edges easier to see, or leave it mounted securely. Find the widest part of the saddle and measure straight across from one outer edge to the other, keeping the tape level rather than following the curved surface. Record this as the saddle’s maximum width. If you also need its length, measure in a straight line from the front tip to the rearmost point. State clearly whether you measured the whole saddle or only its usable seating area; manufacturers may define dimensions differently.
- For an English horse saddle, identify the maker’s reference points. Place the saddle upright on a stable stand or padded surface. A common English-saddle convention is to measure in a straight line from the nailhead at the pommel to the center of the cantle at the rear. Use the tape as a direct line, not along the seat’s curve, and note the result in inches. Some makes or models specify different reference points, so follow the maker’s instructions when they are available. Do not estimate the size from the outside length of the saddle or from the flap.
- For a Western horse saddle, check the maker’s method before measuring. Western saddle seat sizing is commonly given in inches, but the precise starting and ending points can vary by maker and design. Find the manufacturer’s stated measurement points, then measure the straight distance between them across the seat as directed. Do not assume that an English saddle’s pommel-to-cantle method applies to a Western saddle. If the reference points are not marked or described, contact the maker or a saddle shop rather than recording a guess as a standard seat size.
- Check the measurement against the actual fit. A bicycle saddle can be the right width on paper and still feel wrong because its shape, height, angle, or fore-and-aft position does not suit you. Make only small setup changes at a time and test them on a familiar, safe ride. For a horse, the rider’s seat measurement is only one part of the decision. The saddle must also sit appropriately on that horse and allow the horse to move comfortably. Have a qualified saddle fitter assess the fit if you are uncertain, if the saddle shifts, or if the horse shows signs of discomfort.
Common Mistakes
Confusing rider measurements with saddle measurements. Sit-bone spacing is a measurement of the rider; saddle width is a measurement of the product. They are related, but they are not the same number. Likewise, a horse saddle’s seat size is not a measurement of the horse’s back or the saddle tree.
Using a soft or sloping surface for a bicycle impression. A cushioned sofa can spread pressure and blur the marks, while a surface that tilts can make you load one side more than the other. Use a firm, level support and sit in a repeatable position. If you cannot identify two clear impressions, repeat the test or seek help rather than selecting a saddle from an uncertain result.
Measuring along a curve when a straight measurement is required. A tape draped over the top of a bicycle saddle or along a horse saddle seat will give a different result from a straight-line measurement. Keep the tape taut and use the specified endpoints. For a bicycle saddle, measuring across a diagonal instead of its widest point also makes comparisons unreliable.
Assuming all manufacturers use identical conventions. Saddle widths can be listed at different points, and horse saddle makers may give their own seat-measuring instructions. Record how you measured, and compare products only when their figures use compatible methods. A number without its units and reference points is of limited use.
Buying from a measurement alone. A body measurement narrows the choices but cannot account for all comfort or fit factors. Do not ignore persistent discomfort on a bicycle or a poor fit on a horse because the number seems correct. A suitable model and correct setup still need to be confirmed.
Tips
- Write down the date, units, and method with each result. For example, note whether a bicycle saddle width is its maximum outside-to-outside width.
- Repeat a home sit-bone measurement at least once. Similar results are more useful than a single impression that is difficult to read.
- When comparing bicycle saddles, check the shape and width together. A central channel or cutout changes the saddle’s feel, but it does not change how its maximum outside width is measured.
- Use the same posture for repeat measurements. Riders who spend most of their time upright may load the saddle differently from riders in a low, forward position.
- For a horse saddle, keep the saddle supported and stable while measuring. Do not balance it precariously or pull on straps, billets, or other parts to hold it in place.
- When in doubt, take the saddle and your notes to a reputable bike shop, saddle maker, or qualified horse saddle fitter. Bring the make and model if you know them.
Troubleshooting
The bicycle impressions are too faint to measure: Check that the surface is firm and that the material can show pressure marks. Sit down slowly, settle your weight evenly, and stand without shifting sideways. Try again with help positioning the material. If it remains unclear, a shop’s measuring device or a professional fitting is a better option than guessing.
The two bicycle marks look different or the result changes each time: Your sitting position may be shifting, or you may be reading broad impressions inconsistently. Repeat the test with your feet supported and your torso in the same posture. Mark the centers rather than measuring from the outer edges. If your numbers still vary substantially, treat the home method as inconclusive.
The measured bicycle saddle width does not match a product listing: Confirm whether the listing gives maximum width, and check the units. Measure the saddle at its widest point, straight across. If the listing does not state where or how width is measured, ask the seller or manufacturer before comparing it directly with another model.
The horse saddle has no obvious measurement marks: Look up the exact brand and model and request its seat-sizing instructions. A ruler placed at guessed points may produce a number that does not correspond to the maker’s size. If the saddle is unmarked or its history is unknown, a saddle shop can help identify its style and measurement convention.
The measured size seems right, but riding remains uncomfortable: Recheck the measurement, then look beyond it. For a bicycle, saddle shape, position, clothing, and riding posture may be involved; persistent pain or numbness is a reason to stop and seek qualified fitting advice. For a horse, do not keep riding in a saddle that seems unstable or is associated with discomfort. Arrange an assessment of the complete horse-and-saddle fit.
Frequently Asked Questions
How do I measure my sit bones at home?
Use a firm, markable surface on a level seat, sit in a repeatable riding posture, and measure from the center of one clear sit-bone impression to the center of the other. Repeat if the marks are unclear.
Is bicycle saddle width the same as sit-bone width?
No. Sit-bone width describes your body, while saddle width is the saddle’s outside measurement. Use the bicycle saddle maker’s guidance and consider riding posture and saddle shape when choosing a width.
How is an English saddle seat commonly measured?
A common method is a straight measurement from the pommel nailhead to the center of the cantle, recorded in inches. Check the specific maker’s instructions because reference points can differ.
Can I use the same method to measure a Western saddle?
Not automatically. Western saddle makers may define different start and end points. Follow the instructions for that saddle’s make and model rather than applying an English-saddle convention.
Does horse saddle seat size tell me whether it fits my horse?
No. Seat size is about the space for the rider. Fit on the horse depends on the saddle’s construction and how it contacts that horse, so consult a qualified saddle fitter if you are unsure.
Should I measure a bicycle saddle while it is on the bike?
You can, if it is stable and you can access the widest point. Removing it may make the measurement easier, but use the same straight, outside-to-outside method either way.