---
title: "100 fl oz to gal = 0.78125 gal"
description: "100 US fluid ounces is 0.78125 US gallons. The arithmetic, a table of nearby values, and a converter for any other number."
url: https://atoneplace.net/convert/100-fl-oz-to-gallons/
site: "At One Place"
---

# 100 fl oz to gal

**100 US fluid ounces in US gallons: 100 fl oz = 0.78125 gal**

gal = fl oz × 0.0078125

100 US fluid ounces is 0.78125 US gallons. To get there, multiply by 0.0078125.

## Values either side

*US fluid ounces near 100, converted to US gallons.*

| US fluid ounces | US gallons |
| --- | --- |
| 80 fl oz | 0.625 |
| 85 fl oz | 0.66406 |
| 90 fl oz | 0.70313 |
| 95 fl oz | 0.74219 |
| 100 fl oz ← | 0.78125 |
| 110 fl oz | 0.85938 |
| 120 fl oz | 0.9375 |
| 125 fl oz | 0.97656 |
| 150 fl oz | 1.171875 |

## How the conversion works

The relationship is gal = fl oz × 0.0078125. 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 gallon: US liquid gallon. The imperial gallon is about 20% larger.

## Common questions

### What is 100 fl oz in US gallons?

100 fl oz is 0.78125 gal.

### How do you convert US fluid ounces to US gallons?

Multiply by 0.0078125.

## Related pages

- [US fluid ounces to US gallons](https://atoneplace.net/convert/fl-oz-to-gallons/)
- [100 gal to fl oz](https://atoneplace.net/convert/100-gallons-to-fl-oz/)
- [80 fl oz to gal](https://atoneplace.net/convert/80-fl-oz-to-gallons/)
- [85 fl oz to gal](https://atoneplace.net/convert/85-fl-oz-to-gallons/)
- [90 fl oz to gal](https://atoneplace.net/convert/90-fl-oz-to-gallons/)
- [95 fl oz to gal](https://atoneplace.net/convert/95-fl-oz-to-gallons/)
- [110 fl oz to gal](https://atoneplace.net/convert/110-fl-oz-to-gallons/)
- [120 fl oz to gal](https://atoneplace.net/convert/120-fl-oz-to-gallons/)
- [125 fl oz to gal](https://atoneplace.net/convert/125-fl-oz-to-gallons/)
- [150 fl oz to gal](https://atoneplace.net/convert/150-fl-oz-to-gallons/)

## 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/)