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Liquid nitrogen is at about -195.8 °C (-320 °F, 77.3 K) at normal atmospheric pressure. That figure is its boiling point, so the liquid is always boiling at room conditions and holds that temperature as it boils off. The NIST Chemistry WebBook gives the normal boiling point of nitrogen as 77.34 K.
What is the temperature of liquid nitrogen in Celsius?
The normal boiling point of nitrogen is 77.34 K, which converts to -195.81 °C, or about -320.5 °F. Safety data sheets round it: the Linde liquid nitrogen SDS lists a boiling point of -195.8 °C. Both the rounded -196 °C and the more exact -195.8 °C are correct for everyday lab use. Another NIST-cited measurement gives 77.4 K, so quote no more precision than your purpose needs.
Liquid nitrogen boiling temperature and what sets it
“Liquid nitrogen temperature” is a boiling-point temperature. The word “normal” in “normal boiling point” means measured at standard atmospheric pressure. Because the liquid is held at its boiling point, a vessel of liquid nitrogen at room conditions keeps boiling and stays at that temperature while it does.
Three reference temperatures for nitrogen
NIST lists three phase-change temperatures that frame the liquid. The Celsius and Fahrenheit columns are our conversions from the NIST kelvin values.
| Reference point | Kelvin (NIST) | Celsius | Fahrenheit |
|---|---|---|---|
| Normal boiling point | 77.34 K | -195.81 °C | -320.5 °F |
| Triple point | 63.14 K | -210.01 °C | -346.0 °F |
| Critical temperature | 126.19 K | -147.0 °C | -232.5 °F |
Read together, the table shows what “how cold is liquid nitrogen” actually means. Liquid nitrogen sits near the warm end of its liquid range at normal pressure: roughly 14 K above the triple point, and about 49 K below the critical temperature, above which nitrogen cannot exist as a liquid however much it is compressed. The Linde SDS gives a melting point of -210 °C and a liquid density of 808.5 kg/m³ at the boiling point and 1 atm.
Does nitrogen expand with heat?
Yes, and the largest effect is the change of state. Carleton University Environmental Health and Safety states that liquid nitrogen expands 695 times in volume when it vaporizes. Our liquid nitrogen and cryogen handling guide quotes a ratio of 694:1; the two figures describe the same roughly 700-fold expansion.
That expansion links the temperature to two hazards. In a sealed or unvented container, boil-off raises pressure, and Carleton warns of explosion risk if liquid nitrogen is stored in unvented containers, which is why containers carry pressure relief. Carleton also advises that dewars not be filled beyond 80% of capacity. In a closed room, the gas produced is the second hazard, covered next.
Is it true that nitrogen displaces oxygen?
Yes. The Linde safety data sheet classifies nitrogen as a simple asphyxiant and carries a label warning that it may displace oxygen and cause rapid suffocation. Carleton EHS describes the same hazard: the large gas volume from vaporizing liquid creates a risk of oxygen deficiency that may cause unconsciousness. The SDS also notes that the asphyxiation hazard is often overlooked and should be stressed in operator training, and that oxygen detectors should be used where asphyxiating gases may be released. Containers are fitted with pressure relief devices and should be used only in well-ventilated areas.
Can you touch liquid nitrogen with your bare hands?
No. This page does not describe any technique for contact. The cited safety documents say the opposite. Carleton EHS states that liquid nitrogen vapor can rapidly freeze skin tissue and eye fluid, causing cold burns, frostbite and permanent eye damage even after brief exposure. The SDS likewise lists cold burns and frostbite from contact with the liquid. Both sources point to protective equipment instead of bare skin: a full face shield over safety glasses or goggles, loose-fitting insulated or leather gloves, long sleeves and trousers without cuffs, and tongs to withdraw objects from a cryogenic liquid. For glove material questions, see our glove breakthrough time and permeation data guide.
From temperature to hazard: where each point is documented
For lab, shipping and handling staff, the useful chain is: boiling point of -195.8 °C, boils continuously at room conditions, expands about 695-fold as gas, displaces air in enclosed spaces and builds pressure in sealed vessels. The checklist below maps each link to the document that states it, so you can find the same line on your own supplier’s safety data sheet.
| Item to find | What the cited documents state |
|---|---|
| Boiling point | Linde SDS: -195.8 °C; NIST: 77.34 K |
| Hazard classification | Linde SDS: simple asphyxiant; may displace oxygen and cause rapid suffocation |
| Contact hazard | Linde SDS and Carleton EHS: cold burns and frostbite |
| Eye and hand protection | Linde SDS: cold insulating gloves with a face shield or eye protection; Carleton EHS: face shield over safety glasses or goggles, loose-fitting insulated gloves |
| Pressure relief | Linde SDS: containers have pressure relief devices; Carleton EHS: pressure relief needed, explosion risk in unvented containers |
| Oxygen monitoring | Linde SDS: use oxygen detectors where asphyxiating gases may be released |
| Fill level | Carleton EHS: no more than 80% of dewar capacity |
If a cryogen is part of a cold-storage workflow, also see temperature excursions, what a cryovial is, and how dry ice and compressed gas cylinders are handled in their own guides.
Common misunderstandings
“Liquid nitrogen is -196 °C at any pressure”
The -195.8 °C figure is the normal boiling point, measured at normal atmospheric pressure. It is a property of nitrogen at that condition, not a fixed temperature at all pressures.
“Nitrogen is harmless because it is not toxic”
The hazard is not toxicity but displacement. The SDS classes it as a simple asphyxiant for exactly that reason.
“A brief touch is safe”
Carleton EHS says even brief exposure of skin or eyes to the vapor can cause cold burns, frostbite or permanent eye damage.
“The liquid and the gas look different, so you can see the danger”
The SDS describes the asphyxiation hazard as often overlooked, which is why it recommends oxygen detection and operator training rather than relying on observation.
FAQ
How cold is liquid nitrogen in Fahrenheit and kelvin?
About -320.5 °F and 77.34 K at normal atmospheric pressure (NIST).
What is the boiling temperature of liquid nitrogen?
The normal boiling point is 77.34 K (-195.81 °C). The liquid is at this temperature while it boils.
Why does liquid nitrogen keep boiling at room temperature?
Room temperature is far above its boiling point, so any heat reaching the liquid vaporizes it; each liter of liquid becomes roughly 695 times that volume of gas (Carleton EHS).
Does nitrogen displace oxygen?
Yes. It is a simple asphyxiant that can displace oxygen in enclosed spaces (Linde SDS).
Sources
- NIST Chemistry WebBook, Nitrogen, phase change data, checked 2026-10-29.
- Carleton University Environmental Health and Safety, Liquid Nitrogen Safety, checked 2026-10-29.
- Linde (Refrigeration & Oxygen Co.) liquid nitrogen safety data sheet, checked 2026-10-29.
