Attoliter is 1e-18 liter units.
Attoliters to Cups Converter — aL to cup
Convert Attoliter (aL) to Cup (cup) using the exact conversion factor (1 attoliter = 4.226753e-18 cup). See the formula, worked examples, conversion table, history, and common uses.
Attoliters to Cups converter
Converter
Volume Converter
Convert metric, US customary, imperial, cooking, dry, and industrial volume units.
Context values
Some unit families need one extra value for a physically accurate result.
A US customary cup is 236.5882365 milliliters.
Result = input x 1e-21 / 0.0002365882365.
Volume uses the cubic meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Attoliters to Cups
Attoliter and Cup appear side by side at fuel pumps and on beverage labels, since the US measures liquids in gallons while most of the world uses liters. Specifically: Attoliter is 1e-18 liter units, and a US customary cup is 236.5882365 milliliters.
Formula
cups = attoliters × 4.226753e-18
This factor comes from each unit's defined relationship to the category's base unit: 1 attoliter equals 1e-21 base units, and 1 cup equals 0.0002365882365 base units, so dividing one by the other gives the direct attoliter-to-cup factor of 4.226753e-18.
Simple example
1 aL × 4.226753e-18 = 4.226753e-18 cup
1 attoliter = 4.226753e-18 cups.
Real-world example
10 aL × 4.226753e-18 = 4.226753e-17 cup
10 attoliters = 4.226753e-17 cups.
Conversion table
| Attoliter (aL) | Cup (cup) |
|---|---|
| 1 aL | 4.226753e-18 cup |
| 5 aL | 2.113376e-17 cup |
| 10 aL | 4.226753e-17 cup |
| 25 aL | 1.056688e-16 cup |
| 50 aL | 2.113376e-16 cup |
| 100 aL | 4.226753e-16 cup |
Reverse conversion: Cup to Attoliter
4.226753e-18 cup × 2.365882e+17 = 1.000000038 aL
4.226753e-18 cups = 1.000000038 attoliters.
attoliters = cups × 2.365882e+17
For a page dedicated to this direction, see Cup to Attoliter.
Understanding the Attoliter (aL)
Attoliter is 1e-18 liter units.
Understanding the Cup
Cup (cup) measures volume. The US customary cup used in cooking is defined as exactly 240 milliliters (a rounded culinary standard, not the older 236.588 mL legal cup). It is classified as a US customary unit (culinary).
Where it's used: United States (recipes and cooking measurement)
Cooking cup vs. legal US cup. US recipes commonly round the cup to 240 mL for convenience, while the precise legal US cup (used to derive fluid ounces, pints, etc.) is 236.588 mL — a small but sometimes noticeable difference in precise baking.
Uses of the Cup today
- US recipe and cooking measurement
- Nutrition labeling serving sizes
- Baking, where volume-based flour/sugar measurement is still common in the US
History of the Cup
The cup as a cooking measure grew out of household and community cookbook conventions in 19th-century America, standardizing what had been ad hoc measurements ('a teacup of flour') into a fixed volume.
The US FDA uses a rounded 240 mL 'metric cup' for nutrition labeling purposes, distinct from the slightly smaller legal/customary cup (236.588 mL, exactly 1/16 of a US gallon) used elsewhere.
Historical origin. Cup was not the invention of a single named person; it developed through the process described above.
Cup — sources
- US FDA — Reference Amounts Customarily Consumed — Uses the 240 mL rounded cup for nutrition labeling.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many cups are in 1 attoliter?
1 attoliter equals 4.226753e-18 cups, using the exact defined conversion factor rather than an estimate.
How do I convert attoliter to cup?
Multiply the attoliter value by 4.226753e-18. The converter above does this instantly to whatever precision you set.
How do I convert cup back to attoliter?
Use the reverse factor: 1 cup equals 2.365882e+17 attoliters. You can also use the swap control in the converter above to flip the direction instantly.
What is a attoliter?
Attoliter (aL) is a unit of volume.
What is a cup?
Cup (cup) measures volume. The US customary cup used in cooking is defined as exactly 240 milliliters (a rounded culinary standard, not the older 236.588 mL legal cup). It is classified as a US customary unit (culinary).
Is the attoliter to cup conversion exact?
Yes. The US customary cup used in cooking is defined as exactly 240 milliliters (a rounded culinary standard, not the older 236.588 mL legal cup). That fixed definition is what the converter above uses, so any rounding you see is a display choice, not a limitation of the math.
What is the difference between cooking cup vs. legal us cup?
US recipes commonly round the cup to 240 mL for convenience, while the precise legal US cup (used to derive fluid ounces, pints, etc.) is 236.588 mL — a small but sometimes noticeable difference in precise baking.