Why the next size up feels so much bigger

Going from a medium to a large often adds "just an inch". It rarely feels like just an inch. There are two reasons, and both are simple.

Reason one: girth is a line, but stretch is an area

Girth is measured around the toy. What your body accommodates is closer to the whole cross-section, and that grows faster than the tape measure suggests.

So one inch more around means roughly a third more toy. That is why half-inch steps feel sensible and full-inch steps feel like a leap.

Reason two: most size steps change three things at once

Makers usually scale a design up in proportion. The next size is thicker, and it is also longer, and its widest point sits further from the tip. That's three new demands in a single purchase:

• more girth,
• more length,
• and the most girth arriving at a depth you may not have reached before.

Any one of those is a reasonable step. All three together is where people stall, or decide a toy "doesn't fit" when a different shape of the same thickness would have been fine.

What to do about it

Change one thing at a time. Look for a toy that is a little thicker at about the same length, or a little longer at about the same girth. The step after that can change the other.

Look across brands. The size you want often exists in another maker's range, sitting between the two sizes your current brand offers.

Check where the girth sits. A thicker toy whose widest point is near the tip is an easier step than one whose widest point is at the base. See how to read girth at depth.

The Next size tool does this sorting for you. Tell it what you have, and it labels each suggestion with exactly what changes and how big the step is.