Home Ratios 50:1 Mix Ratio

50:1 Mix Ratio Calculator & Chart

Quick Answer A 50:1 mix ratio means 50 parts gasoline to 1 part 2-stroke oil. For 1 gallon of gas, you need 2.6 fl oz (77 mL) of oil. This is the most common ratio for modern 2-stroke equipment.

50:1 Mix Calculator

50:1

Fixed ratio for this calculator

Oil Needed

You Need
2.6
fl oz
for 1 gallon at 50:1 ratio
Milliliters
77
US Fluid Ounces
2.6
Liters
0.077

Need a different ratio? Use our full calculator →

What is a 50:1 Mix Ratio?

A 50:1 mix ratio means you mix 50 parts gasoline with 1 part 2-stroke oil. This creates a fuel mixture that is 2% oil and 98% gasoline by volume. The 50:1 ratio is the industry standard for most modern 2-stroke engines manufactured after 2002.

This leaner ratio (compared to older ratios like 32:1 or 40:1) became possible due to improvements in 2-stroke oil quality and engine technology. Modern synthetic and semi-synthetic oils provide better lubrication with less oil, resulting in cleaner combustion, less smoke, and reduced carbon buildup.

The 50:1 ratio equals approximately 2.6 fl oz (77 mL) of oil per gallon of gasoline, or about 20 mL per liter.

Complete 50:1 Mixing Chart

Use this chart for quick reference when mixing fuel at 50:1 ratio:

US Gallons

Fuel (Gallons) Oil (fl oz) Oil (mL) Oil (Liters)
1 gallon 2.6 fl oz 77 mL 0.077 L
2 gallons 5.1 fl oz 154 mL 0.154 L
2.5 gallons 6.4 fl oz 192 mL 0.192 L
3 gallons 7.7 fl oz 231 mL 0.231 L
4 gallons 10.2 fl oz 308 mL 0.308 L
5 gallons 12.8 fl oz 379 mL 0.379 L
6 gallons 15.4 fl oz 455 mL 0.455 L
10 gallons 25.6 fl oz 757 mL 0.757 L

Liters

Fuel (Liters) Oil (mL) Oil (fl oz)
1 liter 20 mL 0.68 fl oz
2 liters 40 mL 1.35 fl oz
5 liters 100 mL 3.38 fl oz
10 liters 200 mL 6.76 fl oz
20 liters 400 mL 13.53 fl oz

Equipment That Uses 50:1 Ratio

The 50:1 ratio is the most common ratio for modern handheld 2-stroke equipment. Here's what typically uses it:

Chainsaws

Most modern chainsaws including Stihl, Husqvarna, Echo, and Makita models manufactured after 2002.

→ Chainsaw Calculator

String Trimmers

Weed eaters and string trimmers from major brands like Stihl, Echo, Husqvarna, and Shindaiwa.

→ Trimmer Calculator

Leaf Blowers

Handheld and backpack leaf blowers from professional and consumer brands.

→ Blower Calculator

Hedge Trimmers

Gas-powered hedge trimmers and pole pruners from professional landscaping brands.

Edgers

Walk-behind and handheld gas edgers for lawn and garden maintenance.

Other Small Engines

Pole saws, brush cutters, and other 2-stroke powered handheld tools.

Don't Mix Up Your Ratios

Using the wrong ratio can damage your engine. 50:1 is not the same as 40:1 or 32:1.

Compare 50:1 vs 40:1 →

50:1 Ratio FAQs

How much oil for 1 gallon at 50:1?
For 1 gallon of gasoline at 50:1 ratio, you need 2.6 fl oz (77 mL) of 2-stroke oil.
How much oil for 5 gallons at 50:1?
For 5 gallons of gasoline at 50:1 ratio, you need 12.8 fl oz (379 mL) of 2-stroke oil. This is approximately one standard small bottle of 2-stroke oil.
What equipment uses 50:1 ratio?
Most modern 2-stroke equipment uses 50:1 ratio including:
  • Stihl chainsaws and trimmers (post-2002)
  • Husqvarna chainsaws and outdoor power equipment
  • Echo string trimmers and blowers
  • Most leaf blowers, hedge trimmers, and edgers
Always check your owner's manual to confirm.
Can I use 50:1 instead of 40:1?
No, using 50:1 in an engine designed for 40:1 provides less oil (a leaner mix), which can lead to inadequate lubrication and potential engine damage. 50:1 has about 20% less oil than 40:1. Always use the manufacturer's recommended ratio. If unsure, using a slightly richer mix (40:1 instead of 50:1) is safer than going leaner.
Is 50:1 the same as 2%?
Yes, a 50:1 ratio equals 2% oil by volume. This means 2% of your total fuel mixture is 2-stroke oil and 98% is gasoline. You can calculate this as: 1 ÷ (50 + 1) = 0.0196, or approximately 2%.
Can I use any 2-stroke oil for 50:1?
You should use high-quality 2-stroke oil that meets the standards for your equipment. Look for oils that meet JASO FD, ISO-L-EGD, or TC-W3 standards. Modern 50:1 engines benefit from synthetic or semi-synthetic oils. Avoid using regular motor oil (10W-30, etc.) as it's not designed to burn in 2-stroke engines.
How do I mix 50:1 fuel?
To mix 50:1 fuel:
  1. Pour desired amount of gasoline into an approved fuel container
  2. Measure the correct amount of 2-stroke oil (use the chart above)
  3. Add oil to gasoline (not the other way around)
  4. Cap the container and shake for 30 seconds to mix thoroughly
  5. Use within 30 days for best results
View detailed mixing guide →

Related Resources