Fahrenheit to Celsius | °F to °C Converter
The Fahrenheit to Celsius Converter shows the equivalent temperature on the metric scale using the standard formula °C = (°F − 32) × 5/9. It’s useful whenever numbers are given in Fahrenheit—checking international weather, following a science lab, setting oven temps from U.S. recipes, or comparing climate data across regions.
This tool lets you enter any Fahrenheit value and instantly see the Celsius result with sensible rounding so it’s practical for everyday decisions. The goal is fast, accurate translation without mental math—helping you verify forecasts, calibrate cooking, and keep notes in your preferred unit. Type a temperature to get the converted value right away.
Convert Fahrenheit (°F) to Celsius (°C) instantly — with live results and formula steps.
Your temperature
Conversion result
Results interpretation: where our converter helps
- Weather & travel: understand forecasts abroad (e.g., 86 °F → 30 °C).
- Cooking & baking: translate oven temps accurately to metric cookbooks.
- Health checks: convert thermometer readings (fever thresholds differ by scale).
- STEM coursework: quick checks when switching units in lab/work problems.
Use cases & examples
Example 1 — Weather: 86 °F → (86 − 32) × 5/9 = 54 × 5/9 = 30 °C.
Example 2 — Oven temp: 425 °F → (425 − 32) × 5/9 = 393 × 5/9 ≈ 218.3 °C.
Example 3 — Fever check: 101.3 °F → (101.3 − 32) × 5/9 ≈ 38.5 °C.
How our Fahrenheit to Celsius converter works
Formulas, steps & assumptions
Exact linear formula — °C = (°F − 32) × 5/9 and °F = (°C × 9/5) + 32.
Precision — choose 0–3 decimals for display; we always compute at double precision then round for output.
Input handling — when you edit °F, we treat it as the source of truth; when you edit °C, we do the reverse.
Limitations — this covers temperature scales only; it doesn’t convert heat capacity, energy, or “gas mark.”
Quick mental check — °F ≈ °C×2 + 30 is a decent back-of-the-napkin rule near room temperature.
How to convert Fahrenheit to Celsius (and back)
- Enter a temperature in Fahrenheit (°F) or Celsius (°C).
- Select Decimals for output precision.
- We update the other unit instantly as you type—no button to press.
- Use Copy link with inputs to save/share the conversion with your settings.
Formulas
- °F → °C:
°C = (°F − 32) × 5/9 - °C → °F:
°F = (°C × 9/5) + 32
Fahrenheit ↔ Celsius — FAQ
What is the formula to convert Fahrenheit to Celsius?
Use °C = (°F − 32) × 5/9. To go the other way, use °F = (°C × 9/5) + 32.
What is 100 °F in Celsius?
100 °F is (100 − 32) × 5/9 ≈ 37.78 °C.
What is 0 °C in Fahrenheit?
0 °C is (0 × 9/5) + 32 = 32 °F.
How many decimals should we use?
For weather or cooking, 0–1 decimals are fine. For medical or lab work, use 1–2 decimals.
Why do Celsius and Fahrenheit have different zeros?
They’re different historical scales. Celsius uses water’s freezing and boiling points (0 °C and 100 °C), while Fahrenheit sets 32 °F and 212 °F.
Can we convert Fahrenheit to Kelvin directly?
Yes: K = (°F − 32) × 5/9 + 273.15. Kelvin is commonly used in science.
Is the conversion linear across all temperatures?
Yes, both scales are linear, so the relationship stays the same across the range.
What’s a quick mental rule for °F → °C?
Subtract 32 and divide by ~2 for a rough estimate. For example, 86 °F ≈ (86 − 32) ÷ 2 ≈ 27 °C (true value 30 °C).
Fahrenheit to Celsius: practical conversions for weather, cooking, and health
We designed our Fahrenheit to Celsius converter to be fast, precise, and practical. Whether we’re reading a forecast, setting an oven, or logging body temperature, a clean conversion helps us avoid guesswork and repeat measurements.
Where Fahrenheit and Celsius show up in real life
In the U.S., Fahrenheit dominates day-to-day life, while science, engineering, and most of the world use Celsius. Many of us switch contexts several times a week—travel, recipes, medical readings, or classwork—so a reliable conversion is a time-saver.
Anchor points you can memorize
- Freezing: 32 °F = 0 °C
- Room: ~68–72 °F = ~20–22 °C
- Body: 98.6 °F ≈ 37 °C
- Boiling: 212 °F = 100 °C
Accuracy, rounding, and decimals
We compute with full floating-point precision and round to your chosen decimals for display. For clinical or lab work, 1–2 decimals can be appropriate; for cooking or weather, 0–1 is usually sufficient.
Common mistakes and quick checks
- Forgetting to subtract 32 before multiplying by 5/9.
- Rounding too early—always convert, then round.
- Assuming a percentage change—this is a linear scale conversion.
Beyond Fahrenheit and Celsius
Kelvin is the SI base unit for thermodynamic temperature (K = °C + 273.15). If you work in science or engineering, consider converting to Kelvin when absolute differences matter.