What Is Teaspoon US (tsp)?
The Teaspoon US, written as tsp, is a small unit used to measure volume. It is mainly used for cooking and baking in the United States. When a recipe says 1 teaspoon, it usually means 1 Teaspoon US. This helps cooks add the right amount of ingredients like salt, sugar or vanilla.
One Teaspoon US is equal to about 4.93 milliliters. Many kitchen sets round this to 5 milliliters for simplicity, but the exact scientific value is a little smaller.
Definition
The Teaspoon US is a unit of volume in the United States customary system. It is used for both liquid and dry ingredients in the kitchen. In science and nutrition, it can also be used, but milliliters and liters are more common there.
The exact modern definition is:
- 1 Teaspoon US = 1/3 US tablespoon
- 1 Teaspoon US = 1/6 US fluid ounce
- 1 Teaspoon US = 1/48 US cup
- 1 Teaspoon US = exactly 4.92892159375 milliliters (by definition using the US fluid ounce)
For everyday home cooking, people often treat 1 teaspoon as about 5 milliliters, but that is a rounded value, not the exact one.
History / Origin
The Teaspoon US has its roots in real spoons used at the table. Long ago, people did not have standard measuring spoons, so they used common household spoons to measure tea and other foods. Over time, people noticed that spoons were not all the same size, which caused problems for recipes and for medicine.
During the 18th and 19th centuries, doctors, pharmacists and cooks wanted more accurate measures. In the United States, the teaspoon slowly changed from a rough household tool into a fixed unit linked to the fluid ounce and tablespoon.
By the late 19th and early 20th century, standards groups in the US defined the teaspoon as exactly one third of a tablespoon and one sixth of a US fluid ounce. Since the US fluid ounce was later tied to the milliliter, the teaspoon also gained an exact metric value.
Today, the Teaspoon US is a fully defined measuring unit, not just any small spoon from a drawer.
Symbol & Abbreviation
The most common way to write Teaspoon US is:
- tsp (lowercase letters) for teaspoon
Other forms you may see, especially in older or informal recipes, include:
- t
- ts
- teaspoon written out as a full word
In professional recipes and nutrition labels in the US, tsp is preferred, because it is clear and not easily confused with other units. It is important not to mix up:
- tsp for teaspoon
- tbsp or Tbsp for tablespoon
One tablespoon is three times larger than one teaspoon, so confusing them can make a big difference in a recipe.
Current Use Around the World
The Teaspoon US is mainly used in the United States in cookbooks, food blogs and on food packaging. You will find it in recipes for sauces, desserts, drinks and almost every type of dish.
In Canada and some Caribbean countries, many recipes follow US style, so the teaspoon is usually understood as the US teaspoon or as a rounded 5 milliliter metric teaspoon.
In most other countries, such as those in Europe, Asia and Oceania, recipes are often written in metric units like milliliters and grams. However, the idea of a teaspoon is still known, and many of those countries treat a teaspoon as exactly 5 milliliters. This is called the metric teaspoon and is not exactly the same size as the Teaspoon US, even though the difference is small.
In medicine and child care, health groups often warn people not to use household spoons from the drawer. Instead, they suggest using a proper measuring spoon or syringe marked in milliliters, because many home spoons are too big or too small.
Example Conversions
Here are some simple conversion examples using the Teaspoon US. Values are rounded for easy use in the kitchen.
From Teaspoon US to other units
- 1 Teaspoon US ≈ 4.93 mL
- 2 Teaspoons US ≈ 9.86 mL
- 3 Teaspoons US = 1 US tablespoon ≈ 14.79 mL
- 6 Teaspoons US = 2 US tablespoons ≈ 29.57 mL (about 1 US fluid ounce)
- 48 Teaspoons US = 1 US cup ≈ 236.59 mL
From milliliters to Teaspoon US
- 5 mL ≈ 1.01 Teaspoons US (very close to 1 teaspoon)
- 10 mL ≈ 2.03 Teaspoons US
- 15 mL ≈ 3.04 Teaspoons US (about 1 tablespoon)
- 20 mL ≈ 4.06 Teaspoons US
To other kitchen units
- 1 Teaspoon US ≈ 0.333 Tablespoon US
- 1 Teaspoon US ≈ 0.167 US fluid ounce
- 1 Teaspoon US ≈ 0.0208 US cup
In everyday life, many cooks use this handy rule:
- 1 tsp ≈ 5 mL
- 3 tsp ≈ 15 mL ≈ 1 tbsp
Related Units
Several units are closely related to the Teaspoon US.
- Tablespoon US (tbsp) one tablespoon is equal to 3 Teaspoons US. Used for slightly larger amounts like oil or sugar.
- US fluid ounce (fl oz) one fluid ounce is equal to 6 Teaspoons US. Used for liquids such as juice or milk.
- US cup one cup is equal to 48 Teaspoons US. Common in many American baking recipes.
- Milliliter (mL) metric volume unit used worldwide. One Teaspoon US is about 4.93 mL.
- Metric teaspoon usually defined as exactly 5 mL in many countries outside the US.
- Imperial teaspoon older unit in the British imperial system. It is about 5.92 mL, so it is larger than the Teaspoon US.
FAQs
Is a Teaspoon US the same as a regular spoon from my kitchen drawer?
No. A Teaspoon US is a fixed measuring unit. A normal teaspoon from your drawer can be larger or smaller. For accurate cooking or medicine, you should use proper measuring spoons marked with tsp or mL.
Is 1 Teaspoon US equal to 5 milliliters?
Not exactly. The exact value is about 4.93 milliliters. However, many recipe books and medicine labels round this to 5 milliliters because it is easier to remember. For most home cooking, this small difference does not matter.
What is the difference between a Teaspoon US and a metric teaspoon?
The Teaspoon US is about 4.93 mL. The metric teaspoon is usually defined as exactly 5 mL. So the metric teaspoon is slightly larger, but the difference is very small.
How many Teaspoons US are in a Tablespoon US?
There are exactly 3 Teaspoons US in 1 Tablespoon US. This is a basic rule in American cooking measurements.
How many Teaspoons US are in a cup?
There are 48 Teaspoons US in 1 US cup. This is because 1 cup is 8 US fluid ounces and each fluid ounce is 6 Teaspoons US.
Can I use Teaspoon US measurements in baking?
Yes. Most American baking recipes use teaspoons, tablespoons and cups. For best results, use a full measuring spoon set, level off dry ingredients and pour liquids to the marked line.
Why do doctors say to use milliliters instead of teaspoons for medicine?
Doctors prefer milliliters because they are exact and match the markings on syringes and dosing cups. Household teaspoons are not always the right size, so using mL helps avoid giving too much or too little medicine.
Are Teaspoons US used outside the United States?
They are sometimes used in recipes in Canada and on some international food websites. However, most countries now prefer metric units such as milliliters and grams, often using a 5 mL metric teaspoon instead.
How can I quickly convert Teaspoons US to milliliters in my head?
You can use a simple rule. Treat 1 Teaspoon US as about 5 mL. So 2 tsp is about 10 mL, 3 tsp is about 15 mL and 4 tsp is about 20 mL.
Is the Teaspoon US used for both liquids and dry ingredients?
Yes. In American cooking, teaspoons measure both liquids like vanilla and oils and dry items like salt and spices. For very accurate baking, many professionals still prefer to weigh dry ingredients in grams.