12 well plate map template
Twelve wells, ten of them edge wells: the layout is the experiment. Free downloads and an online maker, no signup, they open in Excel and Google Sheets.
A plate map is the written record of what is in each well: the grid, the groups, the controls, decided before anything is pipetted. At 12 wells the map also records the two facts reviewers ask about: which conditions sat in the two interior wells, and what the seeding density was.
Open the online plate map maker Paint wells by group, then export the finished map as Excel or CSV.
Downloads
Plate map template (Excel, XLSX)
Plate map template (CSV)
Plate map template (printable PDF)
Plate map template (PNG image)
Sample list (Excel, XLSX)
Sample list (CSV)
Why a map matters at 12 wells
With only two interior wells, layout is a variable, not a detail. A map written before seeding forces the honest questions while they are still cheap: which conditions get the interior positions on this plate, and how do positions rotate on the replicate? It also carries the seeding density and day, the insert pore size where inserts are used, and the harvest order, which are the four facts that explain most odd 12 well results later.
How to use the map
The map file is a grid, rows A to C and columns 1 to 4, with header fields for plate ID, date, operator, and assay. Mark the fixed positions first: controls and the condition layout, before samples go anywhere. The sample list file is the long form, one row per well for sample ID, contents, concentration, volume, and notes, which pastes cleanly into a lab notebook, a LIMS, or an analysis script.
Related guides
Common questions
Is the template compatible with Excel and Google Sheets?
Yes. The map and sample list download as Excel workbooks, and CSV versions sit at the same paths with a .csv extension. Excel, Google Sheets, and LibreOffice open either format directly.
How should I assign conditions on a 12 well plate?
Treat position as a blocking factor: across replicate plates, rotate which conditions occupy the two interior wells (B2 and B3) and which occupy corners, and record the assignment on the map. One plate proves a layout; rotated replicates prove a result.