Label stock
50.8 × 25.4 mm labels
Two inches by one. If a lab has one box of blank labels in the cupboard, this is usually the size in it.
Why this size became the default
2 × 1 inches is large enough to hold a complete reagent legend and small enough to wrap a bottle without meeting itself. On a 250 mL bottle with a 70 mm barrel it covers about a quarter of the circumference, which is the range where a label is easy to apply straight and easy to read without turning the bottle far.
It is also the size at which a label stops being an index and starts being a document. Nine lines of forty-eight characters is enough for name, concentration, solvent, preparation date, expiry, owner and a hazard line, with room left to set the name larger than the rest.
What this size is
- In inches
- 2 × 1 in. An inch size by origin: 50.8 × 25.4 mm is the exact conversion of it, with nothing rounded.
- Vessels it wraps
- Anything from a 50 mL conical tube upwards, so also a GL45 reagent bottle. The tightest of those has a usable band of about 88 × 55 mm, which this label fits inside.
- Die-cut sheets
- No stock sheet in the editor is cut to this size. On plain paper it packs 33 per A4, 40 per Letter, cut by hand along printed marks.
- Roll stock that carries it
- 50.8 mm, 57 mm, 62 mm, 76.2 mm, 101.6 mm. The narrowest that takes it is 50.8 mm, and a roll narrower than the label is reported as an error rather than trimmed.
What fits on a 50.8 × 25.4 mm label
| Type size | Lines | Plex Sans | Barlow Condensed | Atkinson Hyperlegible | Plex Mono | Space Mono | Courier Prime |
|---|---|---|---|---|---|---|---|
| 4.5 pt | 12 | 64 | 88 | 64 | 51 | 50 | 51 |
| 5 pt | 11 | 57 | 79 | 58 | 46 | 45 | 46 |
| 6 pt | 9 | 48 | 66 | 48 | 38 | 37 | 38 |
| 7 pt | 8 | 41 | 56 | 41 | 32 | 32 | 32 |
| 8 pt | 7 | 36 | 49 | 36 | 28 | 28 | 28 |
| 10 pt | 5 | 28 | 39 | 29 | 23 | 22 | 23 |
The temptation at this size is to fill it
Having room for eleven lines is not a reason to set eleven lines. A reagent label is read under a fume hood by someone wearing glasses that have just fogged, and the thing that makes it readable is contrast between the identifier and everything else, not the number of fields present.
A working rule: one line at 8 pt or larger that says what this is, three to five lines at 5 to 6 pt that say what you need to use it, and nothing that exists only because the field was available in the editor. Anything that belongs to the batch rather than the bottle — supplier lot numbers, certificates, the analyst's name — belongs in the record.
Where a hazard applies, the pictogram earns its space more than any line of text. A GHS pictogram at this size can be 10 mm or more across, which is visible from across a bench in a way that a hazard statement in 5 pt is not.
Common questions
- How many 2 × 1 inch labels fit on a sheet?
- No common die-cut sheet is cut to exactly 50.8 × 25.4 mm, but the editor packs 33 onto plain A4 and 40 onto Letter with cut marks. On rolls it is one of the most widely stocked sizes, on every roll width from 50.8 mm upward.
- Is 2 × 1 inch big enough for GHS labelling?
- For a secondary container in a workplace, generally yes: it holds the product identifier, the pictograms and a hazard statement. It is not the size for a full supplier label under CLP or HCS, which needs signal word, full hazard and precautionary statements and supplier details. Those need 76.2 × 50.8 mm or larger.
Open it in the editor
The editor loads at 50.8 × 25.4 mm with a worked example in place. It runs entirely in your browser: nothing you type is uploaded, and there is no account to make.
Last reviewed 2026-09-13.