Baking Pan Size Converter
Switching pan sizes? Calculate how much to adjust your recipe and baking time.
Original Pan
New Pan
Pan Size Area Reference
| Pan | Area (sq in) | Relative to 9" round |
|---|---|---|
| 8" round | 50 sq in | 0.79x |
| 9" round | 64 sq in | 1.00x (baseline) |
| 10" round | 79 sq in | 1.23x |
| 8" square | 64 sq in | 1.00x |
| 9" square | 81 sq in | 1.27x |
| 9x13" rect | 117 sq in | 1.83x |
| 11x7" rect | 77 sq in | 1.20x |
Key Equivalences
9" round = 8" square — these two pans have nearly identical areas and are interchangeable in most recipes without adjustment.
Two 9" rounds = one 9x13" rectangle — if you want a sheet cake instead of a layer cake, use 1.8x the batter in one 9x13 pan.
How to swap one baking pan for another
Recipes are written for a specific pan, but most of us don't own that exact dish. What actually matters is the area (for how thick the batter sits) and the volume (for whether it will overflow). This converter compares the pan your recipe calls for with the pan you actually have and tells you the ratio, so you can scale the batter up or down and know whether the depth — and therefore the bake time — will change.
The rule of thumb: if your replacement pan has a similar area, the batter depth stays the same and you can bake for roughly the original time. If the new pan is smaller, the batter sits deeper and needs a lower temperature or longer time so the middle cooks before the edges burn; if it's larger, the batter is shallower and bakes faster, so start checking 5–10 minutes early.
Tips
Never fill a cake or loaf pan more than about two-thirds full — batter with leavening needs headroom to rise. When you move to a deeper pan, drop the oven by about 25°F (15°C) and extend the time. A skewer or thermometer beats the clock every time: cakes are done around 205–210°F (96–99°C) in the centre.
Frequently asked questions
Can I use a 9-inch round instead of an 8-inch?
Yes, but a 9-inch round has about 27% more area, so the batter spreads thinner and bakes faster — check 5–8 minutes early. Going the other way (8-inch for a 9-inch recipe) makes a deeper cake that needs a little longer and a slightly lower temperature.
How do I convert a round recipe to a square pan?
A square pan holds more than a round of the same width (a square has roughly 27% more area than a round with the same measurement). This tool shows the exact ratio so you can adjust the batter amount rather than guess.
Does changing the pan change the oven temperature?
Only if the batter depth changes noticeably. Same depth, same temperature; deeper batter, lower and slower; shallower batter, hotter and faster is unnecessary — just start checking earlier.
Written by Nicolas Martin. Last updated July 2026 · How we keep our tools accurate →