12-Well Plate Tool

12-Well Plate Template & Layout Maker

Describe your layout — or ask for a blank template — and get a publication-ready 12-well plate figure: the 3 × 4 grid with rows A–C and columns 1–4, colour-coded groups and a legend.

Example 12-well plate figures

A blank template and a treatment layout in triplicate, each a real render — click a card to load the prompt that drew it.

Blank template

Treatment layout

What is a 12-well plate template?

A 12-well plate template is a figure of the 12-well culture plate grid — 3 rows lettered A to C and 4 columns numbered 1 to 4, with well A1 at the top left. Coloured by group with a legend it becomes a plate layout recording which treatment or control each well received.

Key facts

A 12-well plate has 3 rows lettered A to C and 4 columns numbered 1 to 4.
It is built on the same 127.76 × 85.48 mm ANSI/SLAS footprint as a 96-well plate.
A Corning 12 well is 22.1 mm across with about 3.8 cm² of growth area; Thermo Fisher lists 3.5 cm².
Corning recommends 0.76–1.14 mL of medium per well; Thermo Fisher gives 1–2 mL.

How does the 12-well plate maker work?

Describe the layout

Name each column or well — vehicle in column 1, three doses in columns 2–4, rows A–C as triplicates. The tool knows the 3 × 4 grid and its headers; a blank request gives an empty template.

Pick a style

The default is a flat publication plate — white background, one outline weight, a legend. Or choose grayscale print, pastel, dark slide, hand-drawn or 3D labware.

Refine and export

The figure opens in your workspace, where you can recolour groups, edit the legend on the canvas, regenerate with a changed layout and export in high resolution.

12-well plate dimensions, volumes and cell numbers

The footprint is standardized; the well figures below are the manufacturers' own, so two sources are given where they differ.

Dimension	Value	Source
Grid	3 rows (A–C) × 4 columns (1–4)	Plate convention
Footprint	127.76 × 85.48 mm	ANSI/SLAS 1-2004
Well diameter (bottom)	22.1 mm	Corning CLS-AN-209
Growth area per well	3.8 cm² (Corning); 3.5 cm² (Thermo Fisher)	Corning CLS-AN-209; Thermo Fisher
Total well volume	6.9 mL	Corning CLS-AN-209
Working volume	0.76–1.14 mL (Corning); 1–2 mL (Thermo Fisher)	Corning CLS-AN-209; Thermo Fisher
Seeding density	About 0.1 × 10⁶ cells per well	Thermo Fisher
Cells at confluency	About 0.5 × 10⁶ per well	Thermo Fisher
Well pitch	Not standardized — set by the manufacturer	ANSI/SLAS 4-2004 covers 96, 384 and 1536 wells only

Cell numbers depend on the cell line — treat the seeding and confluency figures as a starting point, and quote well dimensions from the datasheet of the plate you used.

12-well vs 6-well vs 24-well plates

The three formats share one footprint. Each step from 6 to 12 to 24 wells roughly halves the growth area per well, trading cells per condition for conditions per plate.

Feature	6-well	12-well	24-well
Grid	2 rows × 3 columns	3 rows × 4 columns	4 rows × 6 columns
Row letters	A–B	A–C	A–D
Growth area (Corning)	9.5 cm²	3.8 cm²	1.9 cm²
Working volume (Corning)	1.9–2.9 mL	0.76–1.14 mL	0.38–0.57 mL
Typical use	Culture, transfection, colonies	Culture, transfection, coverslips	Culture, transfection, imaging

Growth areas and volumes from Corning application note CLS-AN-209, flat-bottom plates.

Where are 12-well plate figures used?

A 12-well plate suits small treatment sets with triplicates, and the layout figure keeps the treatments and replicates straight.

Treatments in triplicate

Four conditions down the columns, three replicates down the rows — the classic 12-well design, readable in one small figure.

Coverslip imaging and differentiation

Wide wells take coverslips or longer cultures; the layout records which well carries which stain or time point.

Lab notebooks and protocols

Print a blank template to fill in at the bench, or keep a filled plate layout as the record of what went where.

Common questions about 12-well plates

How many rows and columns does a 12-well plate have?

Three rows lettered A to C and four columns numbered 1 to 4 — 3 × 4 = 12 wells. Wells run from A1 at the top left to C4 at the bottom right.

What is the surface area of a 12-well plate well?

About 3.8 cm² by Corning's figure and 3.5 cm² by Thermo Fisher's, with a Corning well 22.1 mm across at the bottom. Use your plate's datasheet whenever results are normalised per area.

How much medium goes in a 12-well plate?

Corning recommends 0.76–1.14 mL per well (6.9 mL total well volume); Thermo Fisher gives 1–2 mL of growth medium.

How many cells should I seed in a 12-well plate?

Thermo Fisher's reference figure is about 0.1 × 10⁶ cells per well, reaching about 0.5 × 10⁶ at confluency. Adjust for your cell line's size and doubling time.

What are the dimensions of a 12-well plate?

The same 127.76 × 85.48 mm ANSI/SLAS 1-2004 footprint as a 96-well plate. The well spacing is not in the standard — ANSI/SLAS 4-2004 covers 96, 384 and 1536 wells — and is set by each manufacturer.

How should I describe a 12-well plate layout?

Name the columns, rows or single wells. "Vehicle in column 1, 1 µM in column 2, 5 µM in column 3, 10 µM in column 4, rows A–C as triplicates" places every group exactly.