Microwave wattage calculator

Convert cooking times by microwave wattage.

Package instructions often assume a specific microwave power, usually 1000W or 1100W. This calculator estimates the adjusted time for your microwave so a 700W, 800W, 900W, 1000W, or 1200W oven can follow the same starting point more accurately.

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Original cooking time

Adjusted cooking time

0:00

Enter a wattage pair and cooking time to calculate the estimate.

Designed for common package instructions

Use it for frozen meals, leftovers, mug recipes, snacks, and reheating directions that list a microwave wattage different from yours.

Great for everyday reheating

Convert package directions for snacks, leftovers, frozen meals, and quick lunches when your microwave wattage does not match the label.

Quick answers without guesswork

Use the calculator and charts to get a better starting time, then follow package stirring, resting, and temperature checks for safer results.

Illustrated microwave conversion example showing 1100 watt instructions converting to 1000 watt and 700 watt cooking times.
See the concept at a glance: the same package instructions can lead to different starting times depending on your microwave wattage.
Popular charts

Common microwave wattage conversions

These chart pages give quick reference tables and internal links for users who want the answer without filling out the calculator every time.

1100W to 700W Open chart 1100W to 800W Open chart 1100W to 900W Open chart 1100W to 1000W Open chart 1000W to 700W Open chart 1000W to 800W Open chart 1000W to 900W Open chart 1200W to 700W Open chart 1200W to 1000W Open chart
Learn more

Helpful microwave cooking guides

How the conversion works

Learn the formula, why wattage changes cooking time, and why the result should be treated as an estimate.

Read the guide

How microwaving works

Understand water molecules, hot spots, cold spots, standing time, and why uneven heating can happen.

Read the guide

Find your microwave wattage

Use the door label, owner manual, product plate, or model search to identify the wattage of your microwave.

Read the guide

Safe microwave cooking

Understand stirring, standing time, cold spots, hot spots, and when a thermometer matters.

Read the guide

Internal cooking temperatures

Use a quick chart for poultry, leftovers, ground meat, seafood, eggs, casseroles, and more.

View the chart