The formula to convert degrees Fahrenheit (°F) to degrees Celsius (°C) is:

°C = (°F - 32) × 5/9

So, to convert 80 degrees Fahrenheit to Celsius, we substitute the value into the formula:

°C = (80 - 32) × 5/9

°C = (48) × 5/9

°C = 26.66666... (repeating)

Therefore, 80 degrees Fahrenheit is approximately equal to 26.67 degrees Celsius.