Batch lab label maker

The list is the run

A copy count produces N identical labels, which is exactly what a run of samples must not be. Adding a sequence number helps, but only if the whole run is of one thing — and it rarely is.

Here a run is a list of rows: each row names something and says how many of it. Replicate numbering restarts inside each row, so the output reads Blank 1, Blank 2, Tris-HCl 1, Tris-HCl 2, Tris-HCl 3 — matching how they are called out at the bench rather than a single sequence you have to decode against a note.

From a list to a printed sheet

1. Write the runOne row per thing, with its replicate count. A quick “Blank” button is there because blanks are in almost every run.
2. Choose how the number looksPlain, leading zeros, letters, or position in run. Each option is previewed using the actual run, so nothing has to be imagined.
3. Decide where the number goesIts own block on the label — movable, resizable, colourable — or appended to a field.
4. Pick the outputOne exact-size page per label for a thermal roll, or a sheet layout that starts at whichever cell your part-used sheet is up to.
5. Print at 100%Sheet output places each label at its true position on A4 or Letter. Any scaling at the printer moves every label at once.

What the run guarantees

One page per label

Thermal output writes a separate exact-size page for every label in the run, so nothing depends on the driver's idea of copies.

Same numbering everywhere

Browser print and PDF export take their pages from the same builder, so a run cannot come out numbered in one and identical in the other.

Consistent width

Leading zeros are sized to the largest number the run reaches, so no label changes shape partway through.

Blocked, not fudged

If a row's name does not fit the label, the run does not print. Nothing is shrunk or trimmed to make it work.