30 degrees Fahrenheit is equal to -1.1111 degrees Celsius.
To convert 30°F to Celsius, you subtract 32, then multiply the result by 5/9. This process adjusts the Fahrenheit scale relative to Celsius, accounting for the different zero points and unit sizes.
Conversion Tool
Result in celsius:
Conversion Formula
The formula to convert Fahrenheit to Celsius is: C = (F – 32) × 5/9. This works because the Fahrenheit and Celsius scales start at different zero points, and their units are different sizes. Subtracting 32 adjusts for the offset between freezing points of water.
Multiplying by 5/9 scales the temperature difference from Fahrenheit units to Celsius units, since 1 Fahrenheit degree is smaller than 1 Celsius degree.
For example, with 30°F:
- Subtract 32: 30 – 32 = -2
- Multiply by 5/9: -2 × 5/9 = -10/9 ≈ -1.1111°C
Conversion Example
- Convert 50°F to Celsius:
- 50 – 32 = 18
- 18 × 5/9 = 90/9 = 10°C
- Convert 70°F to Celsius:
- 70 – 32 = 38
- 38 × 5/9 ≈ 21.1111°C
- Convert 15°F to Celsius:
- 15 – 32 = -17
- -17 × 5/9 ≈ -9.4444°C
- Convert 0°F to Celsius:
- 0 – 32 = -32
- -32 × 5/9 ≈ -17.7778°C
- Convert 85°F to Celsius:
- 85 – 32 = 53
- 53 × 5/9 ≈ 29.4444°C
Conversion Chart
| Fahrenheit (°F) | Celsius (°C) |
|---|---|
| 5.0 | -15.0000 |
| 10.0 | -12.2222 |
| 15.0 | -9.4444 |
| 20.0 | -6.6667 |
| 25.0 | -3.8889 |
| 30.0 | -1.1111 |
| 35.0 | 1.6667 |
| 40.0 | 4.4444 |
| 45.0 | 7.2222 |
| 50.0 | 10.0000 |
| 55.0 | 12.7778 |
The chart list temperatures in Fahrenheit on the left column, with their Celsius equivalents on the right. You can find the Fahrenheit value you want and see the matching Celsius temperature without calculation.
Related Conversion Questions
- What is 30 degrees Fahrenheit in Celsius with decimals?
- How cold is 30°F in Celsius scale?
- Is 30°F below freezing in Celsius?
- How do you convert 30 F to Celsius quickly?
- What Celsius temperature equals 30 degrees Fahrenheit?
- Does 30°F correspond to positive or negative Celsius?
- How much colder is 30°F compared to 0°C?
Conversion Definitions
Fahrenheit: Fahrenheit is a temperature scale where water freezes at 32 degrees and boils at 212 degrees under standard conditions. It uses degrees Fahrenheit (°F) as units, mainly used in the United States and some Caribbean countries for weather and cooking temperature measurements.
Celsius: Celsius is a temperature scale that sets the freezing point of water at 0 degrees and the boiling point at 100 degrees under standard atmospheric pressure. Celsius degrees (°C) are widely used worldwide for scientific and everyday temperature readings, especially in most countries outside the US.
Conversion FAQs
Why does the formula subtract 32 when converting Fahrenheit to Celsius?
The Fahrenheit scale sets 32°F as the freezing point of water, unlike Celsius which uses 0°C. Subtracting 32 shifts the scale so the zero point align with Celsius. Without subtracting 32, the temperature difference calculation would be incorrect.
Can this formula be used for temperatures below zero Fahrenheit?
Yes, the formula works for all temperatures in Fahrenheit, including below zero. The subtraction and multiplication adjust the scale properly regardless of positive or negative input values.
Why multiply by 5/9 in the conversion?
One Fahrenheit degree is smaller than one Celsius degree. The ratio 5/9 converts the size of the Fahrenheit unit difference into Celsius units. Multiplying by 5/9 scales the temperature difference correctly after adjusting the zero point.
Are there any exceptions or special cases for this conversion?
No exceptions exist for this linear conversion formula. It applies to all temperatures on the Fahrenheit scale, because the scales have a constant ratio and offset for their units.
How accurate is this formula for scientific purposes?
The formula is mathematically exact for converting temperature values. Accuracy depends on the precision of input numbers and decimal rounding, but the formula itself provides exact conversions.