Layout units

PowerPoint stores geometry in EMU (English Metric Units), 914400 to the inch. The slide sizes, helpers and constants on this page are exported from pptx-ts.

Standard layouts

STANDARD_LAYOUTS holds the four sizes pptx.layout accepts without defineLayout(). A new presentation uses LAYOUT_16x9.

Name	Inches	EMU
LAYOUT_16x9	10 × 5.625	9144000 × 5143500
LAYOUT_16x10	10 × 6.25	9144000 × 5715000
LAYOUT_4x3	10 × 7.5	9144000 × 6858000
LAYOUT_WIDE	13.333 × 7.5	12192000 × 6858000

Each entry carries widthIn, heightIn, widthEmu and heightEmu. LAYOUT_WIDE is 40/3 inches wide, which converts to exactly 12192000 EMU. A width typed as 13.333 converts to 12191695 EMU, so use the preset.

import TsPptx, { STANDARD_LAYOUTS, inchesToEmu } from "pptx-ts"

const pptx = new TsPptx()
pptx.layout = STANDARD_LAYOUTS.LAYOUT_WIDE // the same as pptx.layout = "LAYOUT_WIDE"

const wide = STANDARD_LAYOUTS.LAYOUT_WIDE
inchesToEmu(wide.widthIn) // 12192000, the same as wide.widthEmu

Unit helpers

Helper	From	To	Constant
inchesToEmu(inches)	inches	EMU	EMU_PER_INCH
pointsToEmu(points)	points	EMU	EMU_PER_POINT
pixelsToEmu(pixels, dpi)	pixels at dpi	EMU	EMU_PER_INCH
percentToEmu(percent, axisEmu)	a percentage of axisEmu, 50 for half	EMU	none
coordToEmu(value, axisEmu)	a coordinate in any form x, y, w and h accept	EMU	the ones above, and DEFAULT_PX_PER_INCH for "px"
emuToInches(emu)	EMU	inches	EMU_PER_INCH
emuToPoints(emu)	EMU	points	EMU_PER_POINT
emuToPixels(emu, dpi)	EMU	whole pixels at dpi	EMU_PER_INCH
ptToHundredths(pt)	points	hundredths of a point, the unit of a font size	HUNDREDTHS_PER_POINT

• The helpers that return EMU, pixels or hundredths round to a whole number. emuToInches and emuToPoints do not round.
• NaN or an infinite input throws InvalidOptionError with the code coord/non-finite.
• An EMU result outside MIN_COORDINATE_EMU to MAX_COORDINATE_EMU throws coord/out-of-range.
• A dpi of 0 or less throws coord/not-positive.
• coordToEmu throws coord/invalid-format for a string it cannot parse, such as "2cm". It reads a bare number above 1000 as inches and warns coord/bare-number-is-inches.

Constants

Constant	Value	Meaning
EMU_PER_INCH	914400	EMU in an inch
EMU_PER_POINT	12700	EMU in a point
POINTS_PER_INCH	72	points in an inch
DEFAULT_PX_PER_INCH	96	pixels in an inch for the "px" coordinate unit
HUNDREDTHS_PER_POINT	100	stored units in a point of font size, character spacing or line spacing
ANGLE_UNITS_PER_DEGREE	60000	stored angle units in a degree
PERCENT_SCALE	100000	the stored value of 100%
FIXED_PCT_PER_PERCENT	1000	the stored value of 1%
MIN_COORDINATE_EMU	-27273042329600	the smallest coordinate DrawingML allows
MAX_COORDINATE_EMU	27273042316900	the largest coordinate DrawingML allows

Positions and sizes

Every object is placed by x, y, w and h, in any of the units listed in Core concepts. A negative w or h measures the box the other way, left of x or above y. ts-pptx writes that box with a positive size and a flip, because PowerPoint refuses to open a file that stores a negative size.

// Runs upward, from (1, 3) to (2.5, 1)
slide.addShape("line", { x: 1, y: 3, w: 1.5, h: -2 })

You pass	Box written	Flip written
x: 1, y: 3, w: 1.5, h: -2	x: 1, y: 1, w: 1.5, h: 2	vertical
x: 4, y: 1, w: -3, h: 1	x: 1, y: 1, w: 3, h: 1	horizontal
x: 4, y: 1, w: -3, h: 1, flipH: true	x: 1, y: 1, w: 3, h: 1	none

• A flip that comes from a negative size combines with the flipH or flipV you set. Either one alone mirrors the object, and the two together cancel.
• Unit strings behave the same way: w: "-2in" and w: "-25%" are handled like a negative number.
• Shapes, text boxes, images, media and group frames get the flip. Charts, tables, OLE objects, 3D models and zooms get the corrected box with no flip.
• addConnector() takes two endpoints instead of a size, and derives its box and flips from them the same way. See Place the endpoints.