Question 1

What's the difference between saddle size and saddle width?

Accepted Answer

Saddle width is specifically the lateral dimension that supports your sit bones - usually measured in mm (130 to 180+). Saddle size loosely refers to length plus width and shape. For fit, width is the critical dimension: too narrow and your sit bones fall off the rails; too wide and your inner thighs chafe.

Question 2

How do I measure sit-bone width at home?

Accepted Answer

Sit on a piece of firm corrugated cardboard for 10-15 seconds, leaning slightly forward to mimic your cycling posture. Stand up and measure the distance (centre-to-centre) between the two deepest impressions. Repeat twice and average the readings. Alternatively, use a memory-foam pad or a specialised measuring kit from a bike shop.

Question 3

Why does riding position affect the recommended saddle width?

Accepted Answer

The more you rotate your pelvis forward - as in an aggressive road position - the further apart your contact points move relative to your sit-bone spacing at rest. Race positions generally add ~15 mm to sit-bone width, endurance adds ~20 mm, and upright commuting adds ~25 mm or more.

Question 4

Do men and women need different saddle widths?

Accepted Answer

Not inherently. Women on average have slightly wider sit bones, but the overlap between genders is substantial. Always size by your actual measured sit-bone width - gender-specific saddles primarily differ in shape (cutout size, nose profile), not width range.

Question 5

My saddle feels fine but I get numbness - is it the wrong width?

Accepted Answer

Possibly. Numbness usually indicates soft-tissue pressure, meaning either the saddle is too narrow (so pressure transfers to the perineum instead of the sit bones) or tilted nose-up. Check sit-bone alignment first, then try a saddle with a pressure-relief cutout or channel.

Question 6

How close to the recommended width does a saddle need to be?

Accepted Answer

Within ~5-10 mm is usually fine - most brands step in 10 mm increments. If your target is 150 mm and the brand offers 145 or 155, either should work; the 145 will feel more racy, the 155 more supportive. Prioritise shape and cutout over splitting hairs on width.

Question 7

Should I use this calculator or the saddle-size calculator?

Accepted Answer

Use whichever matches your preferred approach. This saddle-width tool emphasises brand cross-reference and specific stocked widths. The saddle-size calculator adds riding-style and gender adjustments for more nuanced padding recommendations. Both arrive at similar results for most riders.

Brand	Stocked widths (mm)	Notes
Specialized	143 / 155 / 168	Ass-o-meter at dealers; Mimic and Power ranges
Bontrager	138 / 145 / 155 / 165	Four widths - finest granularity among majors
Fizik	140 / 145 / 155	"Spine concept" shape categories (Bull/Chameleon/Snake)
Selle Italia	135 / 145 / 155	ID Match system; Lady variants common
Ergon	145 / 155	Standard + Wide; narrow two-option line

Brand	Stocked widths (mm)	Notes
Specialized	143 / 155 / 168	Ass-o-meter at dealers; Mimic and Power ranges
Bontrager	138 / 145 / 155 / 165	Four widths - finest granularity among majors
Fizik	140 / 145 / 155	"Spine concept" shape categories (Bull/Chameleon/Snake)
Selle Italia	135 / 145 / 155	ID Match system; Lady variants common
Ergon	145 / 155	Standard + Wide; narrow two-option line

Saddle Width Calculator

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