100 g of baking soda is about 5.6 tablespoons, approximately. One tablespoon of baking soda weighs 18 g, and one teaspoon weighs 6 g, so the arithmetic is simple: 100 g divided by 18 g per tablespoon gives 5.6 tablespoons. The figure comes from King Arthur Baking, measured spooned and levelled, and every result on this page is labelled approximate. Keep the scale nearby for anything that has to be exact.
Leavening is the one place in baking where a tablespoon is not a casual measure. Baking soda, baking powder, yeast and cream of tartar all work by chemistry, and the chemistry only works in the right proportion. Too little and the bake stays flat; too much and it rises fast, collapses, and tastes of metal or soap. That is why the weight matters more here than anywhere else in the kitchen: 18 g per tablespoon is a small number, and a heaped spoon is a large error.
About Baking Soda
Sodium bicarbonate; needs an acid to activate. Leavening cakes, cookies and quick breads with acidic ingredients. Leavening is measured in teaspoons and tablespoons because the amounts are tiny compared with flour and sugar, but tiny does not mean unimportant. A cake that needs one tablespoon of baking soda needs 18 g, and the difference between 18 g and the 20-plus grams a heaped spoon can hold is the difference between a good rise and a collapsed, bitter crumb. Baking soda is the densest leavener in the kitchen at 18 g a tablespoon, and a single extra spoon can leave a metallic taste through a whole cake.
Storage. Airtight container, cool and dry, up to 6 months once opened.
Grams to tablespoons table
The table below converts grams of baking soda into tablespoons, using 18 g per tablespoon. Use it when a recipe gives a weight and you want to measure by spoon, or when a packet tells you the weight and you want to know how many spoonfuls that is. All figures are approximate; verify with a kitchen scale when it matters.
| Grams | Tablespoons |
|---|---|
| 10 g | 0.6 tbsp |
| 20 g | 1.1 tbsp |
| 25 g | 1.4 tbsp |
| 30 g | 1.7 tbsp |
| 40 g | 2.2 tbsp |
| 50 g | 2.8 tbsp |
| 60 g | 3.3 tbsp |
| 70 g | 3.9 tbsp |
| 75 g | 4.2 tbsp |
| 80 g | 4.4 tbsp |
| 90 g | 5 tbsp |
| 100 g | 5.6 tbsp |
Tablespoons to grams table
Working the other way round, here is what each spoonful of baking soda weighs. One tablespoon is one sixteenth of a cup, so every figure below is the cup weight of 288 g divided by 16. Sixteen tablespoons make one cup, which is why the last row of the table matches the cup weight exactly.
| Tablespoons | Grams |
|---|---|
| 1 tablespoon | 18 g |
| 2 tablespoons | 36 g |
| 3 tablespoons | 54 g |
| 4 tablespoons | 72 g |
| 5 tablespoons | 90 g |
| 6 tablespoons | 108 g |
| 7 tablespoons | 126 g |
| 8 tablespoons | 144 g |
| 9 tablespoons | 162 g |
| 10 tablespoons | 180 g |
| 16 tablespoons | 288 g |
Cups to grams for reference
Most recipes switch between cups and tablespoons, so here is the same ingredient measured in cups. Use this table when a recipe gives a cup amount and you want to weigh it, or when you have already measured in tablespoons and want to check the total.
| Cups | Tablespoons | Grams |
|---|---|---|
| 1/4 cup | 4 tablespoons | 72 g |
| 1/3 cup | 5 tablespoons plus 1 teaspoon | 96 g |
| 1/2 cup | 8 tablespoons | 144 g |
| 2/3 cup | 10 tablespoons plus 2 teaspoons | 192 g |
| 3/4 cup | 12 tablespoons | 216 g |
| 1 cup | 16 tablespoons | 288 g |
| 1 1/2 cups | 24 tablespoons | 432 g |
| 2 cups | 32 tablespoons | 576 g |
Worked examples
A layer cake that has to rise evenly
A two-layer sponge that calls for 1 tablespoon of baking soda needs 18 g, sifted into the flour before the wet ingredients are added. Sifting matters: it breaks up lumps and spreads the leavening evenly through the batter, so the cake rises level instead of doming on one side. Weighing the 18 g rather than spooning it means the rise is the same every time you bake the recipe, which is what you want from a cake you make more than once.
A big batch of pancakes for the weekend
A pancake batter for a family breakfast often uses 2 tablespoons of baking soda, about 36 g, whisked into the dry ingredients. Two tablespoons across a large bowl of batter is a modest dose, but it is what gives pancakes their lift and their tender crumb. Mix it through the flour first so it is distributed evenly instead of sitting in pockets, and cook the batter soon after mixing — the reaction starts the moment the liquid hits the leavening, and waiting wastes it.
Doubling a bread or muffin recipe
Doubling a recipe that uses 1 tablespoon of baking soda means 2 tablespoons, about 36 g — and this is where weighing earns its keep, because leavening does not scale by feel. If the recipe gives the weight instead, 100 g of baking soda is about 5.6 tablespoons, which is a bulk amount: enough for many bakes, not one. Weigh the doubled amount on the scale, sift it into the flour, and keep every other ingredient doubled by the same factor, because changing one ingredient without changing the others throws the recipe out of balance.
How the figure is measured
Baking Soda is measured spooned and levelled: spoon it loosely into the tablespoon, then sweep the top flat with the back of a knife. Do not scoop directly from the bag or jar, because scooping packs the ingredient down and a scooped spoon can weigh far more than a spooned one. The spoon-and-level method is the one the source data assumes, so it is the method that makes the numbers on this page true.
The cup weight of 288 g comes from King Arthur Baking. The tablespoon figure is that cup weight divided by 16, rounded to one decimal place, which is why the table is consistent from one row to the next. All results are approximate: brand, grind, humidity and temperature all move the real weight a little, so when a recipe has to work the first time, weigh the ingredient on a kitchen scale and use these numbers as a guide.
Scaling the recipe up and down
Tablespoons scale cleanly once you know the weight of one spoon. A recipe that calls for 8 tablespoons of baking soda needs 144 g, and doubling it to 16 tablespoons means 288 g, exactly one cup. Halving works the same way: 4 tablespoons is 72 g, and 2 tablespoons is 36 g. The rule that matters is to scale every ingredient by the same factor, because changing one ingredient without changing the others throws the recipe out of balance.
When a recipe gives a weight instead of spoonfuls, work backwards: 100 g of baking soda is about 5.6 tablespoons, and 50 g is about 2.8 tablespoons. Round to the nearest half tablespoon when you are measuring by hand, and accept that the result will be a gram or two off, which is fine for most cooking. For large amounts, stop counting spoons and switch to a cup measure or a scale: counting out 16 tablespoons is slow and error-prone, and a cup is faster and more accurate.
If you do not have a scale
If you do not own a kitchen scale, the tables on this page are your best substitute — but they only work if the spoon is filled the right way. Use a proper set of measuring spoons, fill the tablespoon spooned and levelled, and level it off with the back of a knife. Do not use a tablespoon from the cutlery drawer, do not heap the spoon, and do not scoop straight from the bag, because each of those habits adds an unpredictable amount. For a single tablespoon the error is small in absolute terms but large as a percentage, so for baking and for any recipe you plan to repeat, a basic digital scale is worth the small cost: it turns every conversion on this page from an approximation into a certainty.
Frequently asked questions
How many tablespoons is 100 g of baking soda?
About 5.6 tablespoons. The calculation is 100 g divided by 18 g per tablespoon, which gives 5.6. In practice, measure that many level tablespoons and accept that the result will be a gram or two off, or weigh the ingredient directly if the recipe needs to be exact.
How many grams is 1 tablespoon of baking soda?
One tablespoon of baking soda weighs 18 g, approximately. The figure comes from dividing the cup weight of 288 g by 16, since one tablespoon is one sixteenth of a cup. One teaspoon is 6 g, and one cup is 288 g.
How many tablespoons of baking soda are in a cup?
There are 16 tablespoons in one US cup, so one cup of baking soda is 16 tablespoons and weighs 288 g. Half a cup is 8 tablespoons (144 g), a quarter cup is 4 tablespoons (72 g), and three quarters of a cup is 12 tablespoons (216 g).
Is 18 g per tablespoon exact or approximate?
It is approximate. The cup weight of 288 g comes from King Arthur Baking, measured spooned and levelled, and the real weight of a tablespoon varies with brand, grind, humidity and how the spoon is filled. For most cooking the approximation is fine, and for baking or any recipe that has to work the first time, verify with a kitchen scale.
What happens if I use too much baking soda?
Too much leavening makes a batter rise fast and then collapse, because the bubbles grow too big to hold their shape, and the finished bake can taste metallic or soapy. The fix is prevention: weigh 18 g per tablespoon instead of spooning, and level the spoon. If you have already added too much, the only honest fix is to scale up the rest of the batter to match, which is rarely practical — so measure carefully the first time.
Does baking soda lose strength in storage?
Yes, gradually. Airtight container, cool and dry, up to 6 months once opened. Keep the tub sealed and dry, away from heat and steam, and replace it if bakes start coming out flat despite correct measuring. A quick check is to drop a little into hot water or vinegar and watch for fizz — no fizz means no lift left, and it is time for a fresh tub.
Common mistakes to avoid
- Scooping directly from the tub, which packs the powder down and makes a spoonful weigh far more than a spooned one.
- Leaving the spoon heaped instead of levelling it, which adds an unpredictable extra amount every time.
- Measuring leavening with a damp spoon, which starts the reaction in the spoon and wastes its power before it reaches the batter.
- Storing the tub open or near the stove, where humidity and heat weaken it over time.
The thread running through all of these is the same: leavening only works when it is measured accurately and kept dry. Measure baking soda spooned and levelled, level it off, and check the weight on a scale when the bake has to be right, and the numbers on this page will serve you well.