---
title: "21 tbsp to cup = 1.3125 cup"
description: "21 tablespoons is 1.3125 US cups. The arithmetic, a table of nearby values, and a converter for any other number."
url: https://atoneplace.net/convert/21-tablespoons-to-cups/
site: "At One Place"
---

# 21 tbsp to cup

**21 tablespoons in US cups: 21 tbsp = 1.3125 cup**

cup = tbsp × 1/16

21 tablespoons is 1.3125 US cups. To get there, multiply by 0.0625.

## Values either side

*Tablespoons near 21, converted to US cups.*

| Tablespoons | US cups |
| --- | --- |
| 17 tbsp | 1.0625 |
| 18 tbsp | 1.125 |
| 19 tbsp | 1.1875 |
| 20 tbsp | 1.25 |
| 21 tbsp ← | 1.3125 |
| 22 tbsp | 1.375 |
| 23 tbsp | 1.4375 |
| 24 tbsp | 1.5 |
| 25 tbsp | 1.5625 |

## How the conversion works

The relationship is cup = tbsp × 1/16. Both units measure volume, so the conversion is a fixed factor that never changes. The figure is exact rather than approximate: since the international yard and pound agreement of 1959, an inch is defined as exactly 25.4 millimetres and a pound as exactly 0.45359237 kilograms, and every other imperial and US customary unit here is derived from those two.

> US cup: US legal cup is 240 mL; the customary cup used here is 236.588 mL.

## Common questions

### What is 21 tbsp in US cups?

21 tbsp is 1.3125 cup.

### How do you convert tablespoons to US cups?

Multiply by 0.0625.

## Related pages

- [Tablespoons to US cups](https://atoneplace.net/convert/tablespoons-to-cups/)
- [21 cup to tbsp](https://atoneplace.net/convert/21-cups-to-tablespoons/)
- [17 tbsp to cup](https://atoneplace.net/convert/17-tablespoons-to-cups/)
- [18 tbsp to cup](https://atoneplace.net/convert/18-tablespoons-to-cups/)
- [19 tbsp to cup](https://atoneplace.net/convert/19-tablespoons-to-cups/)
- [20 tbsp to cup](https://atoneplace.net/convert/20-tablespoons-to-cups/)
- [22 tbsp to cup](https://atoneplace.net/convert/22-tablespoons-to-cups/)
- [23 tbsp to cup](https://atoneplace.net/convert/23-tablespoons-to-cups/)
- [24 tbsp to cup](https://atoneplace.net/convert/24-tablespoons-to-cups/)
- [25 tbsp to cup](https://atoneplace.net/convert/25-tablespoons-to-cups/)

## Sources

- Guide for the Use of the International System of Units (SP 811) — NIST (https://www.nist.gov/pml/special-publication-811) [Public domain (US Government)]
- The International System of Units (SI Brochure) — Bureau International des Poids et Mesures (https://www.bipm.org/en/publications/si-brochure)
- Calculated on this page — At One Place (/about/)