Loaf Pan Sizes and Conversions: Amounts for Round and Muffin Pans
Pound cake recipes are often written for an 18 cm loaf pan, but your pan may be 21 cm or a narrow slim type, or you may want to bake small portions in a muffin pan. The trick with loaf pans is to convert by how much batter fits (volume), not by base area. This article covers common loaf pan sizes and volumes, factors between pans, and amounts and baking times when moving to round, muffin and square pans.
Convert loaf pans by volume
Round pans can be converted by the ratio of their base areas, but a loaf pan is deep and its sides flare outward. Comparing only length or width leads to big errors, so compare by how much batter fits (volume).
A loaf pan's volume comes from its inner top dimensions (length × width) and its height. The base of most pans is about 1.5 cm smaller on each side than the top, so calculating it as a frustum (a box with different top and bottom sizes) comes close to the real pan. Batter is generally poured to about 70% of the pan.
Common loaf pan sizes and volumes
| Pan (inner top × height) | Typical volume | Batter (70%) | Ratio to 18×8 cm pan |
|---|---|---|---|
| 16×6.5×5.5 cm (small) | About 480 mL | About 340 mL | ×0.64 |
| 18×6×5.5 cm (slim) | About 500 mL | About 350 mL | ×0.66 |
| 18×8×6 cm (standard) | About 750 mL | About 530 mL | ×1 |
| 21×8×6 cm | About 880 mL | About 620 mL | ×1.17 |
| 24×8×6 cm | About 1,010 mL | About 710 mL | ×1.35 |
Even among "18 cm loaf pans," a slim 6 cm-wide pan holds about two-thirds of the batter of a standard 8 cm-wide one. Bake the same recipe by looking only at length, and the batter overflows the slim pan. When buying a pan, check all three: length, width and height.
Converting an equal-parts recipe (100 g each)
This moves a basic pound cake for an 18×8×6 cm pan, made with 100 g each of butter, sugar, eggs and cake flour (2 eggs), to other pans.
| Pan | Factor | Butter, sugar, flour | Eggs |
|---|---|---|---|
| Slim 18×6×5.5 cm | ×0.66 | 66 g each | 1.3 (about 66 g) |
| 21×8×6 cm | ×1.17 | 117 g each | 2.3 (about 117 g) |
| 24×8×6 cm | ×1.35 | 135 g each | 2.7 (about 135 g) |
| Round 12 cm | ×0.9 | 90 g each | 1.8 (about 90 g) |
| Round 15 cm | ×1.41 | 141 g each | 2.8 (about 141 g) |
| Square 15 cm (5 cm high) | ×1.5 | 150 g each | 3 (about 150 g) |
| Standard muffin pan, 6 cups | ×0.73 | 73 g each | 1.5 (about 73 g) |
In an equal-parts recipe the eggs weigh the same as the rest, so after applying the factor, just weigh beaten egg to match the flour. For baking powder, multiply 1/2 tsp by the factor and round to the nearest 1/4. How to weigh eggs is also explained in Cake Pan Size Conversion.
How many muffins does it make?
Each muffin cup holds little and is filled 70–80% full. Here is roughly how many you can bake with the batter for one 18×8×6 cm loaf pan.
| Muffin pan | Volume per cup | Number from one loaf pan's batter |
|---|---|---|
| Mini (5 cm top diameter) | About 29 mL | About 24 |
| Standard (7 cm top diameter) | About 86 mL | About 8 |
| Large (9 cm top diameter) | About 227 mL | About 3 |
- For a standard 6-cup muffin tray, about ×0.73 of a loaf pan recipe makes exactly 6.
- Paper cup sizes vary by product, so check the base diameter and height and choose the closest match.
- Overfilled cups spill and spread sideways in baking, so 80% is the upper limit.
Baking times when you change pans
| Pan | Typical temperature | Typical time |
|---|---|---|
| Loaf pan 18 cm | 170–180 °C | About 40–45 min |
| Loaf pan 21–24 cm | 170 °C | About 45–55 min |
| Round pan 15 cm | 170 °C | About 40–50 min |
| Standard muffin pan | 170–180 °C | 20–25 min |
| Mini muffin pan | 180 °C | About 12–15 min |
- The shallower or smaller the pan you move to, the shorter the baking time. Start checking at about half the recipe's time.
- Making one cut in the top with a knife about 10 minutes into baking gives a neat split down the center.
- It's done when a bamboo skewer inserted in the center comes out with no wet batter.
Common failures when changing pans, and fixes
| Failure | Common cause | Fix |
|---|---|---|
| Batter overflows | The same amount went into a low-volume pan such as a slim one | Convert by volume and stay within 70% of the pan. Put extra batter in muffin cups |
| Center is underbaked | Too little time in a deep or large pan | Lower by 10 °C, add 5–15 min and check with a skewer |
| Only the top burns | A bigger pan means a longer bake | Cover with foil once it has colored |
| It turned out dry | A small or muffin pan was baked for the original time | Shorten the time and check early with a skewer |
| The center doesn't split | No cut was made before the top dried | Make one cut with a knife about 10 min into baking |
Pound cake gets moister from the day after baking. Even with a different pan, once it's cool, wrap it in plastic and leave it overnight before cutting; the slices come out neat and the flavor settles.
FAQ
- How do I make an 18 cm loaf pan recipe in a 21 cm pan?
- If width and height match (8 cm and 6 cm), about ×1.17. For an equal-parts recipe of 100 g each, that's 117 g each, with 117 g of beaten egg.
- Can I bake a pound cake recipe in a round pan?
- Yes. A recipe for an 18×8×6 cm loaf pan is about ×1.4 in a 15 cm round pan and about ×0.9 in a 12 cm round pan. Round pans are shallower, so adjust the baking time as you watch.
- How many muffins does one loaf pan's batter make?
- For an 18×8×6 cm pan, about 8 in a standard muffin pan (7 cm top diameter) and about 24 in a mini pan.
- What's the volume of a loaf pan?
- A standard 18×8×6 cm pan holds about 750 mL, and you pour in about 70% of that, about 530 mL of batter. Measuring with water gives you the exact volume.
Tools in this article
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