Templates

Sample label template

A sample label is read once, in a hurry, usually while wearing gloves. The identifier has to win the fight for space against everything else on the label.

Open this template in the editor38.1 × 19.05 mm

38.1 × 19.05 mm (1.50 × 0.75 in). The inner outline is the 1 mm safe area. Wraps a 50 mL conical tube or a reagent bottle.

Design the identifier first

The failure mode of sample labelling is not a missing field, it is an identifier you cannot tell apart from the one next to it. “Sample 1” and “Sample 11” look alike at arm's length in a rack; “S-001” and “S-011” do not, because the fixed width means the difference lands in the same column every time.

Fixed-width identifiers are also what makes a run sortable and a barcode scannable without post-processing. The editor's numbering can pad to the width the run actually needs, so a run of 120 gives 001 through 120 and every label is the same shape.

Building a run of sample labels

Open the templateThe size is loaded as 38.1 × 19.05 mm, which wraps a standard 15 mL tube and sits flat on most sample pots.
Type the stem of the identifierEverything the run has in common — the project code, the date, the operator — goes in once.
Turn on the numbered runChoose how the number should look from the live examples. Leading zeros size themselves to the run, so nothing changes width halfway through.
List the different things, if there are anyTwo blanks and three of each condition is a list, not a number. Each row gets its own name and its own replicate count, and the numbering restarts inside each row.
Check the fit, then print at 100%The preflight bar blocks output on anything that would be clipped, so a name that is too long stops the print rather than losing its last word.

How much fits on a 38.1 × 19.05 mm sample label

Type size	Lines	Plex Sans	Barlow Condensed	Atkinson Hyperlegible	Plex Mono	Space Mono	Courier Prime
4.5 pt	9	47	65	47	37	37	37
5 pt	8	42	58	42	34	33	34
6 pt	6	35	49	35	28	27	28
7 pt	5	30	42	30	24	23	24
8 pt	5	26	36	26	21	20	21
10 pt	4	21	29	21	17	16	17

Characters per line and lines per label, measured with the same font metrics the printed label uses. Figures are characters per line, for 38.1 × 19.05 mm. Measured against the string “Tris-HCl 1 M pH 8.0 25 mg/mL 2026-08-24 GS lot B-204 store 4 C”, which is representative of laboratory text rather than of prose.

Common questions

What is a good sample label size?: 38.1 × 19.05 mm suits 15 mL tubes and sample pots. For 1.5 mL microcentrifuge tubes use 25.4 × 12.7 mm, and for cryovials 28.6 × 12.7 mm. The limit is the barrel circumference, not the tube's length.
Can I put a QR code on a sample label?: Yes, and it is generated on your device — no request is made to any server. On a 38 mm label a QR block of about 12 mm leaves room for two lines of text beside it.

Open it in the editor

The editor loads at 38.1 × 19.05 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.

Open the general sample template

Last reviewed 2026-08-24.