Convert Liters to Gallons – Volume Converter
This tool converts a volume value expressed in litres (L) into gallons. It is intended for general-purpose use where a reliable fixed mathematical conversion is required, such as recipes, vehicle fuel estimates, laboratory notes, or rough inventory calculations.
Be aware there are different gallon definitions in common use (for example US liquid gallon and Imperial gallon). The numeric conversion factor differs by definition; consult the methodology and FAQs below to choose the correct gallon standard for your needs.
Governance
Record 029e16fec053 • Reviewed by Fidamen Standards Committee
Interactive Converter
Convert between liter and us gallon with precision rounding.
Quick reference table
| Liter | US Gallon |
|---|---|
| 1 L | GAL 0.2642 gal |
| 5 L | GAL 1.3209 gal |
| 10 L | GAL 2.6417 gal |
| 25 L | GAL 6.6043 gal |
| 50 L | GAL 13.2086 gal |
| 100 L | GAL 26.4172 gal |
Methodology
The converter uses the internationally recognized fixed mathematical relationship between the two units. For the US liquid gallon the exact multiplicative factor used is 0.2641720523581484 when converting from litres to US liquid gallons.
When a different gallon definition is required (for example the Imperial gallon), use the corresponding factor. This implementation assumes a single conversion target unit ID; verify which gallon type is selected in the UI or settings before applying results to regulatory or safety-critical work.
Results are subject to rounding and measurement uncertainty. For high-accuracy requirements reference national measurement standards and ensure instruments are calibrated per NIST guidance and applicable ISO or local standards.
Key takeaways
This converter provides a direct mathematical conversion from litres to gallons using authoritative conversion factors. Confirm which gallon definition you require before using results in regulated or safety-critical contexts.
For high-accuracy needs consult NIST and ISO guidance on units, calibration, and uncertainty and follow workplace safety rules such as those from OSHA when reporting or labelling converted volumes.
Worked examples
5 L × 0.2641720523581484 = 1.320860261790742 US gallons (approx. 1.321 gal when rounded to three decimal places).
10 L × 0.2199692483 = 2.199692483 Imperial gallons (approx. 2.200 gal when rounded to three decimal places).
F.A.Q.
Which gallon does this converter use by default?
The logic uses the target unit ID provided by the UI. Common implementations default to US liquid gallons; confirm the UI label or settings to ensure you are converting to the intended gallon definition. See methodology and examples for both US and Imperial values.
How accurate is the conversion?
The conversion applies an exact mathematical multiplier for the chosen gallon definition. However, practical accuracy depends on the precision of the input value and measurement uncertainty of the instrument that produced it. For regulatory or laboratory work include uncertainty estimates and follow NIST and ISO calibration guidance.
When should I use the Imperial gallon instead of the US gallon?
Use the Imperial gallon when working with sources or regulations from countries that define the gallon that way, historically British contexts, or documents that explicitly state 'Imperial gallon'. For the United States use the US liquid gallon. Check the source or specification when in doubt.
Can I use converted volumes for billing, shipping, or safety reporting?
Converted values are suitable for operational use, but when used in billing, legal documentation, safety data sheets, or regulated reporting, confirm the required unit definition, rounding rules, and whether measurement uncertainty or instrument calibration certificates must be attached in accordance with applicable standards and workplace regulations.
How should I report significant figures and uncertainty?
Report results with a number of significant figures appropriate to the precision of your original measurement. For technical reporting include an uncertainty estimate and reference calibration; follow guidance in NIST publications and ISO standards for expressing measurement uncertainty.
Sources & citations
- NIST Reference on Units and Constants — https://physics.nist.gov/cuu/Units/
- NIST Guide for Use of the International System of Units (SI) — https://www.nist.gov/publications/guide-use-international-system-units-si
- ISO (standards body) — https://www.iso.org
- IEEE Standards Association — https://standards.ieee.org
- OSHA - Hazard Communication Standard and guidance — https://www.osha.gov/hazcom
- ISO 80000-3:2019 — Space and time — https://www.iso.org/standard/64974.html
- NIST SP 811 — Guide for the Use of the International System of Units — https://www.nist.gov/pml/special-publication-811
Further resources
Related tools
Versioning & Change Control
Audit record (versions, QA runs, reviewer sign-off, and evidence).
Record ID: 029e16fec053What changed (latest)
v1.0.0 • 2025-11-07 • MINOR
Initial publication and governance baseline.
Why: Published with reviewed formulas, unit definitions, and UX controls.
Public QA status
PASS — golden 25 + edge 120
Last run: 2026-01-23 • Run: golden-edge-2026-01-23
Versioning & Change Control
Audit record (versions, QA runs, reviewer sign-off, and evidence).
What changed (latest)
v1.0.0 • 2025-11-07 • MINOR
Initial publication and governance baseline.
Why: Published with reviewed formulas, unit definitions, and UX controls.
Public QA status
PASS — golden 25 + edge 120
Last run: 2026-01-23 • Run: golden-edge-2026-01-23
Engine
v1.0.0
Data
Baseline (no external datasets)
Content
v1.0.0
UI
v1.0.0
Governance
Last updated: Nov 7, 2025
Reviewed by: Fidamen Standards Committee (Review board)
Credentials: Internal QA
Risk level: low
Reviewer profile (entity)
Fidamen Standards Committee
Review board
Internal QA
Entity ID: https://fidamen.com/reviewers/fidamen-standards-committee#person
Semantic versioning
- MAJOR: Calculation outputs can change for the same inputs (formula, rounding policy, assumptions).
- MINOR: New features or fields that do not change existing outputs for the same inputs.
- PATCH: Bug fixes, copy edits, or accessibility changes that do not change intended outputs except for previously incorrect cases.
Review protocol
- Verify formulas and unit definitions against primary standards or datasets.
- Run golden-case regression suite and edge-case suite.
- Record reviewer sign-off with credentials and scope.
- Document assumptions, limitations, and jurisdiction applicability.
Assumptions & limitations
- Uses exact unit definitions from the Fidamen conversion library.
- Internal calculations use double precision; display rounding follows the unit's configured decimal places.
- Not a substitute for calibrated instruments in regulated contexts.
- Jurisdiction-specific rules may require official guidance.
Change log
v1.0.0 • 2025-11-07 • MINOR
Initial publication and governance baseline.
Why: Published with reviewed formulas, unit definitions, and UX controls.
Areas: engine, content, ui • Reviewer: Fidamen Standards Committee • Entry ID: 5d43845f43c4