Comfortable Bike Seats: Width, Padding and Sit Bones

“Most comfortable” is not a specification, and the saddle aisle knows it. What the aisle does have is a number — a width in millimetres, printed on the box — and one published definition that complicates it in a useful way.

Here is what we could verify, and one thing we looked for and could not find at all.

The width on the box is not necessarily the width you sit on

The saddle maker SQlab publishes a definition of a saddle’s usable area:

“The area can be used up to the outer points from which the saddle drops more than 1 cm downwards.”

That is a measurable line, and it is worth pausing on. A saddle shell curves away at the sides. Past the point where that curve falls more than a centimetre, SQlab’s position is that the surface is not usable seating area — but it is still width, and it still counts towards the number printed on the packaging.

So two saddles both listed at 155 mm can offer different amounts of surface your sit bones can actually rest on, depending on where each one starts dropping away. That is SQlab’s own definition rather than an industry standard, and we have not seen a second maker publish the same rule. But it is the only published attempt we found to say what the width figure means physically, which makes it worth carrying into a shop.

The number you add is the maker’s, not a standard

The usual fitting path starts with measuring the distance between your sit bones, then adding something to get a saddle width. The measurement is easy and worth taking — we cover it in how to measure sit bone width.

What gets added is where it stops being objective. The bike-fitting company BikeFit, which sells fitting products and discloses as much on the page, writes the relationship as:

“Width of sit bones + X (Defined as added width by manufacture) = the saddle made for you.”

X is defined by the manufacturer. And the figures in circulation do not line up: BikeFit notes that “many suggest adding about 20mm” while describing an example where the rider measured 110 mm and chose a 145 mm saddle, and the saddle maker BiSaddle gives “a 120mm sit bone width suggests a saddle in the 140mm to 150mm range”.

Twenty, thirty-five, or a twenty-to-thirty range, depending on whose page you are on. That comparison is ours and covers those pages only — but it is enough to show there is no constant here to quote.

Padding: we looked, and there is no number

This is the honest finding of the page.

Width has figures. Sit bone spacing has a measurement method. Padding has nothing — we found no published standard, scale, density figure or test for saddle padding on any of the pages we read. Nothing comparable to the width numbers exists to compare two saddles by.

The one statement we have is from BiSaddle, a company that sells saddles: “The correct width is infinitely more important than extra padding.” We are quoting that as a seller’s position on its own product category, not as a finding. It may well be right. We have no way to check it, and neither do you from a product page.

What follows practically is narrower than the usual advice: since padding is the axis we could find no published number for, it is the axis you cannot shop on remotely. Width you can check before paying. Padding you can only find out by sitting on it.

Width is treated as a real variable, at least by some makers

Worth knowing before you assume a model comes one way: SQlab states that “all SQlab saddles are available in up to five different widths”.

That is one maker describing its own range, not a claim about the category. But it establishes something useful — that within a single saddle design, width is a specified option rather than a fixed property, in the same way a shoe last comes in widths. If the saddle you like is sold in one width only, that is a choice its maker made, and it is a fair thing to ask about before buying.

It also means the question to ask a shop is narrower than “what saddle should I get.” It is “which widths does this model come in, and what is the measurement for each.”

Posture decides how much of this applies to you

One condition runs underneath the whole method. BikeFit points out that the sit bone measurement assumes “a 90-degree spine position”, while “the majority of cyclists will have some type of pelvic bend”, so in those rotated positions “the sit bones would not be your main pressure point or measurement point for potential saddle comfort.”

Read the direction of that carefully. It does not say the measurement is worthless. It says its relevance tracks how upright you are — and the more upright you ride, the more it is describing your actual contact. Upright commuting, a city bike, a stationary bike at home: those are exactly the positions where your weight really is on the sit bones.

BikeFit’s own framing points the same way from the other side: it says the measurement misdescribes contact for triathletes and riders in a more aggressive position.

What to check, in order

1. Your own sit bone measurement, taken twice.
2. The saddle’s stated width, and — if the maker publishes it — how much of that width is usable by SQlab’s one-centimetre rule.
3. Whose addition you are using. If you are following a maker’s chart, you are following that maker’s convention.
4. A way to sit on it. Since we could find no published figure for padding, the return policy is doing the job a specification would.

If the saddle is going on a stationary bike, the frame’s own limits are a separate question with its own document — see heavy duty exercise bikes, where the number that matters is printed in the manual rather than the listing.

What we have not done

We have not ridden any of these saddles, fitted anyone, or tested a padding claim. Every figure and quotation above is attributed and linked, and all three sources sell the products they are describing, which is stated where they are quoted. Nothing here ranks saddles, and no saddle is recommended.

Frequently asked questions

Is a saddle's stated width the width you can actually sit on?

Not necessarily, and one maker publishes a rule for the difference. SQlab defines the usable area of a saddle as reaching 'up to the outer points from which the saddle drops more than 1 cm downwards' — so the part of the shell that curves away steeply is width on the spec sheet that your sit bones cannot use. That is SQlab's own definition rather than an industry standard.

Is more padding more comfortable on a bike seat?

On the pages we read we found no published measurement for saddle padding — no standard, no scale, nothing comparable to the width figures. The only statement we have is from the saddle maker BiSaddle, which sells saddles and writes that 'the correct width is infinitely more important than extra padding.' That is a seller's position on its own product category, quoted rather than endorsed.

Does a wider saddle mean a more comfortable one?

Width matched to your own measurement is the part with numbers attached, but nobody we read claims width alone settles comfort. The measurement method itself assumes an upright posture, so how much of your weight is on the sit bones depends on how you ride. Width is the input you can check before buying; it is not a promise about hour three.