ConcreteMetric Navigation Menu
Gallons (AU) to Litres Converter | Free Online Volume Calculator
🪣 Free Online Volume Converter

Gallons (AU) to Litres Converter

Instantly Convert Australian Gallons ↔ Litres — Both Directions

Convert gallons (AU) to litres or litres to gallons (AU) instantly. Get the exact conversion with formula breakdown, reference table, and real-world examples — all free, no sign-up needed.

✅ Gallons (AU) → Litres
✅ Litres → Gallons (AU)
✅ Exact Formula
✅ Reference Table

Gallons (AU) to Litres Converter

The Australian gallon is identical to the Imperial gallon and equals exactly 4.54609 litres. Our converter handles both directions instantly and accurately using the exact internationally defined conversion factor — no rounding, no guesswork.

🪣 What is an Australian Gallon?

The Australian gallon is the same as the Imperial gallon, historically used in Australia before the country adopted the metric system in the 1970s. One Australian (Imperial) gallon equals exactly 4.54609 litres, defined under the Weights and Measures Act. While Australia now officially uses litres, the gallon still appears in older documents, fuel efficiency references, and cross-regional comparisons.

💧 What is a Litre?

The litre (L) is a metric unit of volume widely used across Australia and the world for measuring liquids including water, fuel, and beverages. One litre equals 1,000 millilitres or 1 cubic decimetre (dm³). Since Australia's metrication in the 1970s, the litre has been the standard unit for all liquid measurement — from fuel pricing at the pump to food packaging.

🔢 The Conversion Factor

The exact conversion factor is 1 gallon (AU) = 4.54609 litres, established by international definition. For the reverse, 1 litre = 0.219969 gallons (AU) (= 1 ÷ 4.54609). Note: this is different from the US gallon (1 US gal = 3.78541 L). All conversions on this page use the exact Imperial/Australian gallon value.

🪣 Gallons (AU) to Litres Converter

Choose a direction, enter your value, and get an instant conversion

Converted Value
L
Millilitres
US Gallons
Pints (Imperial)
Cubic Metres
Gallons (AU) vs Litres vs US Gallon — Volume Comparison 1 AU Gal 4.54609 L 1 Litre = 0.21997 gal 1 US Gal 3.78541 L 1 AU Gallon = 4.54609 L 1 Litre = 0.21997 AU gal 1 US Gallon = 3.78541 L AU gallon = Imperial gallon (larger than US gallon)

Figure: Volume comparison — 1 Australian (Imperial) gallon vs 1 litre vs 1 US gallon

Gallons (AU) to Litres Formula

The conversion between Australian gallons and litres uses the exact Imperial gallon definition. The Australian gallon = Imperial gallon = exactly 4.54609 litres, as defined under the international standard. This is not an approximation — both formulas below are mathematically exact. Need other volume conversions? Browse our full converter library at ConcreteMetric.

🪣 Gallons (AU) → Litres Formula

litres = gallons (AU) × 4.54609
Example: 5 gal × 4.54609 = 22.73045 L
Example: 20 gal × 4.54609 = 90.9218 L

💧 Litres → Gallons (AU) Formula

gallons (AU) = litres ÷ 4.54609   (= litres × 0.219969)
Example: 10 L ÷ 4.54609 = 2.19969 gal
Example: 100 L ÷ 4.54609 = 21.9969 gal
💡 Quick Mental Estimate: One Australian gallon is roughly 4.5 litres — just over 4 and a half litres. For a quick estimate, multiply gallons by 4.5 (gives a result within 1% of the exact answer). For litres to gallons, divide by 4.5 as a rough guide, then verify with the exact converter above.

⚡ Quick Reference — Common Gallons (AU) to Litres Conversions

1 gal4.54609 L
2 gal9.09218 L
3 gal13.6383 L
5 gal22.7305 L
10 gal45.4609 L
20 gal90.9218 L
50 gal227.305 L
100 gal454.609 L

Gallons (AU) to Litres Conversion Table

The table below lists commonly needed Australian gallon-to-litre conversions. All values use the exact factor of 1 gal (AU) = 4.54609 L. For litres to gallons, divide by 4.54609 or use the converter above.

Gallons (AU) Litres (L) Millilitres (mL) US Gallons Common Context
0.5 gal2.27305 L2273.05 mL0.6003 US galSmall water bottle (×2)
1 gal4.54609 L4546.09 mL1.2009 US galStandard Imperial gallon
2 gal9.09218 L9092.18 mL2.4019 US galSmall fuel container
3 gal13.6383 L13638.3 mL3.6028 US galGarden watering can
5 gal22.7305 L22730.5 mL6.0047 US galSmall jerrycan
10 gal45.4609 L45460.9 mL12.009 US galStandard jerrycan (approx.)
15 gal68.1914 L68191.4 mL18.014 US galLarge fuel drum (small)
20 gal90.9218 L90921.8 mL24.019 US galSmall water tank
25 gal113.652 L113652 mL30.023 US galMedium aquarium
50 gal227.305 L227305 mL60.047 US galLarge aquarium / drum
100 gal454.609 L454609 mL120.09 US galLarge water tank
200 gal909.218 L909218 mL240.19 US galIndustrial storage
500 gal2273.05 L2273050 mL600.47 US galCommercial tank
1000 gal4546.09 L4546090 mL1200.9 US galLarge industrial storage

Litres to Gallons (AU) Conversion Table

The table below shows common litre values converted to Australian (Imperial) gallons. All values use the exact factor of 1 L = 0.219969 gallons (AU). This is helpful when reading modern metric fuel or water volumes and needing to reference older Imperial gallon records.

Litres (L) Gallons (AU) Pints (Imperial) US Gallons
1 L0.21997 gal1.7598 pt0.26417 US gal
2 L0.43994 gal3.5195 pt0.52834 US gal
5 L1.09985 gal8.7988 pt1.32086 US gal
10 L2.19969 gal17.598 pt2.64172 US gal
20 L4.39938 gal35.195 pt5.28344 US gal
25 L5.49923 gal43.994 pt6.60430 US gal
50 L10.9985 gal87.988 pt13.2086 US gal
100 L21.9969 gal175.98 pt26.4172 US gal
200 L43.9938 gal351.95 pt52.8344 US gal
500 L109.985 gal879.88 pt132.086 US gal
1000 L (1 kL)219.969 gal1759.8 pt264.172 US gal

When Do You Need to Convert Gallons (AU) to Litres?

Even though Australia officially metricated in the 1970s, the Australian (Imperial) gallon still appears in a wide range of practical and historical contexts in 2026. Here are the most common real-world scenarios where this conversion is needed.

⛽ Fuel Efficiency (km/gal → L/100km)

Older Australian vehicle specifications, vintage car guides, and pre-metric fuel consumption figures are often quoted in miles per gallon or kilometres per gallon (AU). Converting these to the modern Australian standard of litres per 100 km requires knowing that 1 AU gallon = 4.54609 L. This conversion is common among classic car enthusiasts and historians.

🌾 Agriculture & Irrigation

Australian farming records, irrigation manuals, and water usage logs from before the 1970s metrication era frequently reference gallons. Tank capacities, spray volumes, and water allocations may still appear in gallons in older property documentation. Converting 500 gallons = 2,273 litres is a routine task for rural landowners reviewing historical water usage data.

🚢 Maritime & Shipping

Fuel capacity, ballast water, and cargo liquid volumes on older vessels and maritime records in Australia may reference Imperial gallons. Modern shipping uses cubic metres and litres, so converting historical logs and legacy technical documents is essential for marine engineers, surveyors, and port authorities working with older fleet data.

🏠 Home Rainwater Tanks

Many older Australian homes have rainwater tanks with capacities stamped in gallons from the pre-metric era. A common tank size of 500 gallons = 2,273 litres, and 1,000 gallons ≈ 4,546 litres. Homeowners checking old tank specifications or comparing with modern litre-rated tanks frequently need this conversion for water planning and compliance purposes.

🌍 Comparing AU vs US Gallons

A common source of confusion is the difference between the Australian (Imperial) gallon and the US gallon. The AU gallon is approximately 20% larger than the US gallon: 1 AU gal = 4.54609 L vs 1 US gal = 3.78541 L. Australians buying US products, reading American recipes, or comparing US fuel economy figures must account for this important difference.

📚 Historical Research & Archives

Australian historical records, colonial-era accounts, early 20th-century industrial reports, and pre-1974 government publications all use Imperial gallons. Researchers, archivists, and historians converting these volume figures to modern litres for analysis, publication, or comparison with contemporary data use this exact conversion regularly.

✅ AU Gallons vs Litres at a Glance: 1 Australian gallon is always larger than 1 litre — specifically 4.54609× larger. So a measurement in gallons will always give a smaller number than the same volume in litres. Conversely, litres converted to gallons always give a smaller number — because gallons are the bigger unit.

Australian Gallons and Litres — Key Facts

📖 Historical Note: Australia used the Imperial gallon as its standard unit of liquid volume until the country adopted the metric system between 1970 and 1988 under the Australian Metric Conversion Act 1970. Petrol prices switched from cents per gallon to cents per litre in 1974. The Imperial gallon was formally defined as exactly 4.54609 litres under the international standards agreement. As of 2026, the litre is the exclusive official unit for liquid volume in Australia.
  • 1 AU gallon = 4.54609 litres (exact — same as Imperial gallon)
  • 1 AU gallon = 8 Imperial pints = 160 Imperial fluid ounces
  • 1 litre = 0.219969 AU gallons (= 1 ÷ 4.54609)
  • 1 AU gallon ≠ 1 US gallon — AU gallon is ~20% larger (4.54609 L vs 3.78541 L)
  • 10 AU gallons = 45.4609 litres
  • 100 AU gallons = 454.609 litres
  • Australia officially metricated liquid volume measurement in 1974
  • A standard 20-litre jerry can holds approximately 4.4 AU gallons
  • A 1,000-litre (1 kL) water tank holds approximately 219.97 AU gallons
⚠️ AU Gallon vs US Gallon Warning: Do not confuse the Australian (Imperial) gallon with the US gallon. The AU gallon = 4.54609 litres, while the US gallon = 3.78541 litres — a difference of about 760 mL per gallon (roughly 16.5%). Always confirm which gallon type is being used when reading international recipes, fuel data, or product specifications to avoid significant errors.

Frequently Asked Questions — Gallons (AU) to Litres

How many litres is 1 Australian gallon?
1 Australian gallon is exactly 4.54609 litres. The Australian gallon is identical to the Imperial gallon, and its value of 4.54609 litres is set by international definition — not an approximation. So 1 AU gal = 4.54609 L. This means one Australian gallon is approximately four and a half litres, or more precisely, 4 litres and 546 millilitres.
How do I convert gallons (AU) to litres?
To convert Australian gallons to litres, multiply the number of gallons by 4.54609. The formula is: litres = gallons (AU) × 4.54609. For example: 5 gallons × 4.54609 = 22.7305 litres. 10 gallons × 4.54609 = 45.4609 litres. 50 gallons × 4.54609 = 227.305 litres. Use the converter at the top of this page for instant results without manual calculation.
How many Australian gallons is 1 litre?
1 litre is equal to approximately 0.219969 Australian gallons (= 1 ÷ 4.54609). Since a gallon is much larger than a litre, you need less than a quarter of a gallon to equal 1 litre. To convert litres to AU gallons, multiply by 0.219969 or divide by 4.54609. Example: 20 litres ÷ 4.54609 = 4.39938 gallons.
Is the Australian gallon the same as the UK gallon?
Yes — the Australian gallon is identical to the UK Imperial gallon. Both equal exactly 4.54609 litres. Australia inherited the Imperial measurement system from the United Kingdom during the colonial period and used the same gallon definition. When Australia metricated in the 1970s, both countries phased out the gallon in favour of the litre, but the underlying definition remains the same: 1 Imperial/Australian gallon = 4.54609 litres.
How is the Australian gallon different from the US gallon?
The Australian (Imperial) gallon and the US gallon are different sizes. The AU gallon = 4.54609 litres, while the US gallon = 3.78541 litres. This means the AU gallon is about 20.1% larger than the US gallon. In practical terms: if a US recipe calls for 1 gallon (3.785 L) and you use an Australian gallon measure (4.546 L), you will add approximately 761 mL too much. Always check which gallon type is specified.
When did Australia stop using gallons?
Australia officially transitioned away from gallons as part of its metrication program under the Metric Conversion Act 1970. Petrol (fuel) prices changed from cents per gallon to cents per litre in July 1974. By the mid-1980s, gallons had been phased out of all official Australian measurements. As of 2026, the litre is the sole official unit for liquid volume in Australia, though gallons still appear in historical documents and older equipment.
How many litres is a 44-gallon drum?
A 44-gallon drum using Australian (Imperial) gallons holds 44 × 4.54609 = approximately 199.9 litres — very close to 200 litres. This is why the standard Australian 44-gallon drum is equivalent to a 200-litre drum in metric terms. The 200-litre steel drum is still widely used in Australia and internationally for industrial storage of liquids, chemicals, and oils.
How many AU gallons in a 1,000-litre tank?
A 1,000-litre (1 kilolitre) tank holds 1,000 ÷ 4.54609 = approximately 219.97 Australian gallons. This is useful for homeowners converting the capacity of a modern 1 kL rainwater tank into the old gallon measurement for comparison with pre-metric tank records. A 1,000-litre tank is nearly 220 AU gallons — or roughly 264 US gallons.

Useful Resources & References

🇦🇺 Australian Bureau of Statistics

The ABS provides official Australian measurement standards, historical metrication data, and statistical references including the transition from Imperial gallons to litres during Australia's metrication program of the 1970s.

Visit ABS →

📏 BIPM — SI Units

The Bureau International des Poids et Mesures (BIPM) is the international body responsible for defining SI units including the litre. Their resources cover official unit definitions and the international relationship between Imperial and metric units.

Visit BIPM →

🇬🇧 UK Government — Imperial Units

The UK government provides official documentation on Imperial units including the gallon — the same definition used historically in Australia. Useful for understanding the exact legal definition of 4.54609 litres per gallon.

Visit UK Gov →

🇺🇸 NIST — US vs Imperial Gallons

The National Institute of Standards and Technology (NIST) provides clear documentation on the difference between US and Imperial (Australian) gallons — essential reading for anyone comparing volume measurements across US and Australian/UK systems.

Visit NIST →