# Liters per 100 km to US miles per gallon converter

> Convert liters per 100 km to US miles per gallon (L/100km to mpg) with the exact formula, a conversion chart and worked steps.

Interactive version: https://www.calcopenly.com/conversion/l-100km-to-mpg
Subject: Unit converters

Liters per 100 kilometers describe fuel used over a fixed distance. A lower number means less fuel for the same route. Restating consumption as US mpg produces a reciprocal relationship, so halving consumption doubles the distance-per-gallon result.

Liters per 100 km and US miles per gallon are not related by a single multiplier: fuel consumption per distance is the reciprocal of distance per fuel, so the conversion uses a formula. 6 L/100 km is 39.2024 mpg (US).

235.214583 is the number of litres per 100 km at 1 US mpg (100 km × 3.785411784 L per gallon ÷ 1.609344 km per mile). Higher mpg means lower L/100 km, and the relationship is a curve, not a straight line.

## Inputs

- **Liters per 100 km (L/100 km)**

## Results

- US miles per gallon (mpg (US)) — main result
- Conversion
- 1 mpg (US) in liters per 100 km (L/100 km)

## Formula

$$
\text{mpg} = \frac{235.214583\ldots}{\text{L/100 km}}
$$

## Worked examples

### 6 L/100 km to mpg (US)

- Liters per 100 km (L/100 km): 6 L/100 km
- **US miles per gallon: 39.2024305556 mpg (US)**
- Checked against: Exact-fraction computation from the legal unit definitions (scripts/gen-pairs.py, Python fractions)

### 12 L/100 km to mpg (US)

- Liters per 100 km (L/100 km): 12 L/100 km
- **US miles per gallon: 19.6012152778 mpg (US)**
- Checked against: Exact-fraction computation from the legal unit definitions (scripts/gen-pairs.py, Python fractions)

### 3 L/100 km to mpg (US)

- Liters per 100 km (L/100 km): 3 L/100 km
- **US miles per gallon: 78.4048611111 mpg (US)**
- Checked against: Exact-fraction computation from the legal unit definitions (scripts/gen-pairs.py, Python fractions)

## Questions

### When would I convert L/100km to mpg?

Liters per 100 kilometers describe fuel used over a fixed distance. A lower number means less fuel for the same route. Restating consumption as US mpg produces a reciprocal relationship, so halving consumption doubles the distance-per-gallon result.

### What is the formula to convert L/100km to mpg?

Divide 235.214583 by the value: 30 US mpg is 235.214583 ÷ 30 = 7.84 L/100 km, and 6 L/100 km is 235.214583 ÷ 6 = 39.2 mpg. The same formula works in both directions because each unit is the reciprocal of the other, scaled.

### How accurate is the liters per 100 km to US miles per gallon converter?

Accuracy depends on your inputs and the method's assumptions. Decimal arithmetic uses 50 significant digits, but estimates, numerical methods and source data can be less precise; the displayed rounding does not remove those limits. It is checked against 3 worked examples whose answers come from independent sources; for example, “6 L/100 km to mpg (US)” is checked against Exact-fraction computation from the legal unit definitions (scripts/gen-pairs.py, Python fractions).

### Where does the method come from?

NIST SP 811 (2008), Guide for the Use of the International System of Units, Appendix B; NIST Handbook 44, Appendix C: General tables of units of measurement; BIPM, The International System of Units (SI Brochure), 9th edition.

## Sources

- [NIST SP 811 (2008), Guide for the Use of the International System of Units, Appendix B](https://www.nist.gov/pml/special-publication-811)
- [NIST Handbook 44, Appendix C: General tables of units of measurement](https://www.nist.gov/pml/weights-and-measures/publications/nist-handbooks/handbook-44)
- [BIPM, The International System of Units (SI Brochure), 9th edition](https://www.bipm.org/en/publications/si-brochure)