Plate planner
Why keep samples off the edge wells of a 96-well plate
The outer 36 wells of a 96-well plate are the usual source of evaporation and position bias. The planner can reserve them, put blanks or controls there, and report it if a sample still lands on the edge.
What “the edge” is
On a 96-well plate the edge is row A, row H, column 1, and column 12: 36 wells. Those wells lose volume faster and sit in a different thermal and optical neighborhood than the interior 60. If unknowns land there, plate effects show up after you pipette, not in the spreadsheet that drew the grid.
The planner treats that as a constraint, not a style. When reserveEdge is on, sample wells are not assigned to the outer ring. Controls and blanks may still use the edge — that is often why you reserved it.
Capacity is arithmetic, not hope
Thirty-six reserved edge wells leave 60 interior wells. Subtract blanks, controls, and extra reserved positions, then divide by replicates. If the table does not fit, the report says so (capacity_samples) instead of quietly overflowing onto A1. If a sample still occupies an edge well, that is listed as edge_occupied. Unsatisfied constraints are part of the result, not a footnote we hide when the map looks full.
The example on this page
The map is the published 24-sample fixture: twelve case, twelve control, eight blanks, four controls, seed 42, edge reserved. No samples on the outer ring. You can load the same CSV in the planner and change the seed; the version string in the export records which layout you kept.
No unsatisfied constraints on this example. Edge-well rules for a 96-well plate layout.