Label stock
Cryogenic label sizes
Cryovial label sizing is decided by the straight run of the barrel, which is always shorter than the vial.
Why the usable height is so small
A cryovial is not a cylinder. It has a threaded neck, a moulding step where the thread ends, often a set of gripping ribs, and a base that may be self-standing or conical. The part that will take a flat rectangular label is the straight section in between, and on a 2 mL internally threaded vial that is around 28 mm — against an overall length near 45 mm.
A label taller than the straight run bridges a moulding step. The bridge leaves a channel underneath, frost forms in the channel, and the label lifts from the middle rather than the edge. That is why an oversized cryo label often fails faster than a correctly sized one of the same material.
Cryovial dimensions and label sizes
| Vial | Barrel | Circumference | Straight run | Label |
|---|---|---|---|---|
| 1.2 mL | ~12.5 mm | ~39 mm | ~22 mm | 28.6 × 9.5 mm |
| 1.8–2 mL | ~12.5 mm | ~39 mm | ~28 mm | 28.6 × 12.7 mm |
| 3.6 mL | ~12.5 mm | ~39 mm | ~40 mm | 28.6 × 19.1 mm |
| 5 mL | ~15.5 mm | ~49 mm | ~45 mm | 38.1 × 19.1 mm |
| Straw / 0.5 mL | ~2.5 mm | ~8 mm | n/a | Cane or goblet label |
What fits on a 2 mL cryovial label
| Type size | Lines | Plex Sans | Barlow Condensed | Atkinson Hyperlegible | Plex Mono | Space Mono | Courier Prime |
|---|---|---|---|---|---|---|---|
| 4.5 pt | 5 | 34 | 48 | 35 | 27 | 27 | 27 |
| 5 pt | 5 | 31 | 43 | 31 | 25 | 24 | 25 |
| 6 pt | 4 | 26 | 36 | 26 | 20 | 20 | 20 |
| 7 pt | 3 | 22 | 30 | 22 | 17 | 17 | 17 |
| 8 pt | 3 | 19 | 27 | 19 | 15 | 15 | 15 |
| 10 pt | 2 | 15 | 21 | 15 | 12 | 12 | 12 |
Internal and external threads change the numbers
An externally threaded cryovial has its thread on the outside of the neck and a cap that screws over it, which keeps the barrel free further up and gives a little more straight run. An internally threaded vial has the thread inside, with a plug-style cap, and the moulding that supports it eats into the barrel.
The practical difference is a few millimetres of usable height on a vial of the same nominal volume — enough to matter when you are choosing between a 9.5 mm and a 12.7 mm label. If a batch of vials changes supplier, re-measure before assuming the old label still fits.
Other cryogenic formats and what they take
- Cryoboxes
- A 2 inch box lid is about 133 mm square. A 63.5 × 25.4 mm label leaves room for a position map alongside it.
- Canes and goblets
- There is no cylindrical surface worth labelling. Use a cane tag or a colour code and keep the detail in the inventory.
- Straws
- Too small for any printed label. Identification is by the straw's own colour and printing, applied at manufacture.
- Bags for controlled-rate freezing
- Flat and generous, but the surface flexes constantly. A label needs a flexible face, not a rigid polyester one.
Common questions
- What size label fits a 2 mL cryovial?
- 28.6 × 12.7 mm. The barrel gives roughly 39 mm of circumference but only about 28 mm of straight run, and the straight run is the limit.
- Can I use a taller label to fit more text?
- Not beyond the straight run. A label that bridges the moulding steps leaves a channel where frost collects, and it lifts from the middle.
Last reviewed 2026-08-24.