What is a microplate?
A flat plate with wells in a grid, each well a small dish that shares its walls with its neighbors, built to one standard footprint so any instrument can hold any plate.
A microplate (also called a microtiter plate or well plate) is a flat plastic plate containing many small wells arranged in rows and columns. Each well holds a sample, a culture, or a reaction, and because every microplate shares the same outside dimensions, plate readers, washers, shakers, incubators, and robots can all handle the same plate without adjustment.
The standard underneath every format
The ANSI/SLAS standards fix the footprint at 127.76 by 85.48 mm and define how wells are positioned from the plate corner. Well counts double and halve along the family: 6, 12, 24, 48, 96, 384, 1536. The 6 well plate is the largest-well member in routine use: 2 rows of 3, wells on a 39.12 mm grid, each well the size of a 35 mm dish. It is the clearest proof that a microplate is a family of formats on one footprint, not a single product.
The 6 well plate in numbers
- Wells: 6, in 2 rows (A to B) by 3 columns
- Well spacing: 39.12 mm center to center
- Footprint: 127.76 by 85.48 mm, the ANSI/SLAS standard
- Culture well: about 34.8 mm across, 9.5 cm2 growth area, 2 to 3 mL working volume
- Surfaces: treated, non-treated, and coated, all sterile with lids
Why the largest wells still exist
The family's history runs toward smaller wells and bigger screens, but the 6 well plate never shrank away, because some work is dish work: colonies picked by eye, cultures watched and fed for weeks, primary cells coaxed into attaching. Miniaturization trades material for throughput, and at the dish end of the family the trade stops making sense. Six wells, honestly used, are a complete experiment.
Who uses 6 well plates
- Cell biology labs: transfection, differentiation, and harvest at blot and prep scale.
- Primary culture and stem cell work: coated surfaces and room to establish fragile cultures.
- Cloning: colonies grown, stained, and picked well by well.
- Teaching labs: one well per student group, visible without a plate reader.
Related guides
Common questions
Is a 6 well plate a microplate?
Yes. A microplate is any plate in the standard footprint family, from 6 to 1536 wells. The 6 well plate is the largest-well member: same outside dimensions, same instrument compatibility, wells on the 39.12 mm grid defined for the format.
What is the difference between a 6 well plate and a 35 mm dish?
Mostly the frame. A 6 well is six 35 mm class wells sharing one standard footprint, so the plate fits incubators, stages, and carriers built for plates, and six conditions travel, stack, and store as one object. A single dish is one condition in a round frame. Labs that run both treat them as interchangeable in area and different in handling.
Why are microplates all the same size?
Because instruments are built once and plates are bought forever. The shared ANSI/SLAS footprint means a reader, washer, or robot arm made this year handles plates from any maker, and a protocol written around one brand survives switching suppliers.
What does 2 by 3 mean on a 6 well plate?
The well layout: 2 rows lettered A to B and 3 columns numbered 1 to 3. Wells are named by row and column, so A2 is the well in row A, column 2. Plate maps and plate map makers use the same addresses.
Are all 6 well plates the same?
No. They share a footprint and grid, but differ in surface (treated, non-treated, coated, and which coating), and in whether the plate is a standard culture plate or a specialty format. Function follows the surface, not the well count.