r.cell.area - GRASS manual

NAME

r.cell.area - Calculates the area of each raster cell for the computational region

KEYWORDS

SYNOPSIS

r.cell.area

r.cell.area --help

r.cell.area output=name units=string [--overwrite] [--help] [--verbose] [--quiet] [--ui]

Flags:

--overwrite: Allow output files to overwrite existing files
--help: Print usage summary
--verbose: Verbose module output
--quiet: Quiet module output
--ui: Force launching GUI dialog

Parameters:

output=name [required]: Output raster of cell areas; Name of output raster map containing cell areas
units=string [required]: Output units; Units for output cell areas; Options: m2, km2, ha, acres, mi2; m2: Square meters; km2: Square kilometers; ha: Hectares; acres: Acres; mi2: Square miles

DESCRIPTION
NOTES
EXAMPLES
SEE ALSO
AUTHOR

DESCRIPTION

r.cell.area is deprecated. Use the built-in area() function in r.mapcalc instead (available since GRASS 7.4). It provides an ellipsoidal cell-area calculation and requires no extra module.

r.cell.area computes the area of each raster cell in the current computational region and writes the result to a new raster map. It is now a thin wrapper around the area() function in r.mapcalc and emits a deprecation warning on every run.

NOTES

The area() function in r.mapcalc returns cell area in square metres using an ellipsoidal model. Multiply by a constant to obtain other units:

r.cell.area units	Equivalent r.mapcalc expression
m2	`r.mapcalc "output = area()"`
km2	`r.mapcalc "output = area() * 1e-6"`
ha	`r.mapcalc "output = area() * 1e-4"`
acres	`r.mapcalc "output = area() / 4046.8564224"`
mi2	`r.mapcalc "output = area() / 2589988.110336"`

EXAMPLES

Compute cell area in square metres (recommended, no module needed):

r.mapcalc "cell_area_m2 = area()"

Compute cell area in hectares:

r.mapcalc "cell_area_ha = area() * 1e-4"

Using r.cell.area (deprecated, emits a warning):

r.cell.area output=cell_area units=ha

AUTHOR

Andrew D. Wickert

SOURCE CODE

Available at: r.cell.area source code (history)

Latest change: Saturday Jun 13 12:23:25 2026 in commit: 90424a70928b64fabea462b85f38e3ef308af8cd