How do you convert Celsius to Fahrenheit?

Multiply the Celsius value by 9/5 and add 32. So 37 °C becomes 37 × 1.8 + 32 = 98.6 °F. The reverse subtracts 32 first, then multiplies by 5/9.

How is Kelvin related to Celsius?

Kelvin uses the same degree size as Celsius but starts at absolute zero. To convert, add 273.15 to a Celsius value. So 0 °C is 273.15 K and 100 °C is 373.15 K.

Can temperatures be negative in Kelvin?

No. Kelvin is an absolute scale where 0 K is the lowest physically possible temperature. The converter flags any entry below 0 K as physically impossible.

Why do labs care about exact conversions?

Protocols are often written in one scale while equipment displays another. An autoclave set to 121 °C is 250 °F; a −80 °C freezer is 193.15 K. Getting the conversion exact prevents protocol errors and sample loss.

What is the autoclave preset based on?

Standard moist-heat sterilisation runs at 121 °C (250 °F, 394.15 K) for 15 minutes at 15 psi, which reliably kills bacterial spores. A faster cycle uses 134 °C for shorter holds.

What is the Temperature Unit Converter (°C / °F / K)?

Convert temperature values between Celsius, Fahrenheit, and Kelvin with lab-relevant presets such as PCR denaturation, autoclave sterilisation, cryogenic storage, and incubator set points. For every laboratory discipline. It runs free in your browser on Gera Tools, with nothing uploaded.

Temperature Unit Converter (°C / °F / K)

Name: Temperature Unit Converter (°C / °F / K)
Creator: Gera Tools
License: https://creativecommons.org/licenses/by/4.0/

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Temperature conversions are constant in the lab: protocols quote one scale, the incubator displays another, and the freezer log uses a third. This converter moves instantly between Celsius, Fahrenheit, and Kelvin and includes presets for the temperatures you actually use at the bench.

How it works

All three scales describe the same physical quantity, so converting is just algebra. Celsius is the reference here:

°F = °C × 9/5 + 32
K  = °C + 273.15

°C from °F = (°F − 32) × 5/9
°C from K  = K − 273.15

Whichever field you edit is converted to Celsius internally, then back out to the other two scales. Kelvin is an absolute scale, so any value below 0 K is physically impossible and is flagged rather than displayed as a valid result.

Lab presets reference table

Set point	°C	°F	K	Context
Liquid nitrogen (vapour)	−150	−238	123	Long-term cell cryopreservation
Ultra-low freezer	−80	−112	193	RNA, enzymes, virus stocks
Standard freezer	−20	−4	253	Antibodies, competent cells
Refrigerator	4	39	277	Reagents, live cultures
Room temperature	22–25	72–77	295–298	Routine bench work
Human body / incubator	37	98.6	310	Mammalian cell culture
Thermophile incubator	55	131	328	Some bacterial growth
PCR denaturation	95	203	368	Double-strand DNA separation
Autoclave (standard)	121	250	394	Moist-heat sterilisation, 15 min
Autoclave (fast cycle)	134	273	407	Prion decontamination, 3 min

Common conversion errors to avoid

Protocol scale mismatch: European protocols almost always use Celsius; US instruments sometimes display Fahrenheit. A PCR annealing step written as 55 °C becomes 131 °F — easy to verify, but a slip here can mean no amplification.

Kelvin in thermodynamics: Buffer pKa calculations and the Henderson-Hasselbalch equation use temperature in Kelvin. Plugging in a Celsius value instead of K will give a subtly wrong pH correction, especially for phosphate and TRIS buffers near physiological temperature.

The −40 identity: −40 is the only point where Celsius and Fahrenheit are numerically equal. It is a useful sanity check for the formula: if your result at −40 °C is not −40 °F, the formula has an error.

Absolute zero: 0 K = −273.15 °C = −459.67 °F. Any converter returning a negative Kelvin value has a bug; the tool flags this case rather than displaying an invalid result.

Whichever field you edit is the master; the other two update immediately from the formulae above.