Quick Answer: Baking Powder Conversions
Standard US tablespoon of baking powder
Expired baking powder is the #1 reason for flat cakes. Test yours now:
- 1. Add 1/2 teaspoon baking powder to 1/4 cup hot water
- 2. Watch for immediate, vigorous fizzing
- 3. Good: Lots of bubbles = Active ✓
- 4. Bad: Few/no bubbles = Replace it! ✗
Shelf life: Unopened: 18 months | Opened: 6-12 months | Store in a cool, DRY place (not the fridge!)
Not all tablespoons are equal! This causes recipe failures:
| Country | 1 Tbsp | Baking Powder Weight | Difference |
|---|---|---|---|
| 🇺🇸 USA | 14.8 ml | 14g | Standard |
| 🇦🇺 Australia | 20 ml | 19g | +35%! |
| 🇬🇧 UK | 15 ml | 14.2g | +1% |
| 🇨🇦 Canada | 15 ml | 14.2g | +1% |
🎯 Solution: Always check recipe origin. Australian recipe? Reduce by 1/3 if using US spoons!
Complete Conversion Chart & Common Uses
| Tablespoons | Grams | Teaspoons | Perfect For |
|---|---|---|---|
| 1/4 tbsp | 3.5g | 3/4 tsp | Single muffin |
| 1/2 tbsp | 7g | 1.5 tsp | 6 cookies |
| 3/4 tbsp | 10.5g | 2.25 tsp | Small loaf |
| 1 tbsp | 14g | 3 tsp | 12 muffins, 8" cake |
| 1.5 tbsp | 21g | 4.5 tsp | 9" round cake |
| 2 tbsp | 28g | 6 tsp | 2-layer cake |
| 3 tbsp | 42g | 9 tsp | Large sheet cake |
| 4 tbsp | 56g | 12 tsp | Wedding cake tier |
The Measuring Spoon Conspiracy
⚖️ Level vs Heaped
Level tablespoon: 14g (correct)
Heaped tablespoon: 21g (+50%!)
Packed tablespoon: 18g (+29%)
Always level with a knife for accuracy
🥄 Cheap Spoons = Bad News
• Dollar store spoons: ±20% variance
• Decorative spoons: Often 30% off
• Old spoons: May be imperial sizes
Invest in proper measuring spoons!
🎂 Bitter, Chemical Taste
Cause: Too much baking powder (heaped spoons or wrong country measure)
Fix: Maximum 1.5 tsp per cup flour. Use a scale!
Emergency save: Add 1 tbsp sugar + pinch of salt to mask
📉 Flat, Dense Cakes
Cause 1: Expired baking powder (do the test!)
Cause 2: Stored near stove (heat kills it)
Cause 3: Old recipe with single-acting powder amounts
Fix: Fresh powder + proper storage + modern ratios
🕳️ Tunnels and Holes
Cause: Overmixing after adding baking powder
Science: First reaction starts immediately, creates big bubbles
Fix: Mix just until combined (lumps are OK!)
Baking Powder vs Baking Soda: Don't Mix Them Up!
🟣 Baking Powder
- • Complete leavener (acid + base)
- • Works in any recipe
- • Double-acting (2 rises)
- • 1 tbsp = 14g
- • Neutral taste when used correctly
🔴 Baking Soda
- • Base only (needs acid)
- • Requires buttermilk, lemon, etc.
- • Single-acting (immediate)
- • 1 tbsp = 17g (different!)
- • Soapy taste if too much
Need to convert? See our Baking Soda Converter
📊 The Ratio Rule
1 cup flour needs 1-1.5 tsp baking powder. That's 125g flour : 4-6g powder
⏱️ Timing Matters
Bake within 20 min of mixing. First reaction already started!
🌡️ Temperature Tip
Cold ingredients slow the reaction. Room temp = better rise
Out of Baking Powder? Make Your Own:
Single-Acting Substitute (use immediately!):
• 1/4 tsp baking soda
• 1/2 tsp cream of tartar
= 1 tsp baking powder
Note: This won't give the second rise of double-acting powder. Work fast and get it in the oven! Need cream of tartar measurements? See our converter.
Common Questions
How much is 1 tbsp baking powder in grams?
1 US tablespoon of baking powder = 14 grams. This assumes a level tablespoon with standard US measuring spoons (14.8ml). Australian tablespoons hold 20ml and weigh about 19g!
Can I use baking soda instead?
No! They're chemically different. Baking soda needs acid (buttermilk, lemon juice) to work. Baking powder already contains acid. Substituting will likely ruin your recipe. If you must, use 1/3 the amount of baking soda PLUS add acid.
Why does my recipe say "heaping tablespoon"?
Old recipes often used heaping measures. A heaping tablespoon is about 21g (50% more!). Modern recipes assume level measurements. When in doubt, use weight for accuracy.
Does altitude affect baking powder amounts?
Yes! At high altitude, gases expand more, so you need LESS baking powder. Reduce by 15-25% above 3,000 feet. See our altitude converter for exact adjustments.