A1 at 72 DPI in pixels: 1684 × 2384

A1 at 72 DPI is 1684 × 2384 pixels

A1 (594 × 841 mm) at 72 DPI is 1684 × 2384 pixels, which is 4 megapixels.

Portrait	1684 × 2384 pixels
Landscape	2384 × 1684 pixels
With 3 mm bleed	1701 × 2401 pixels
Megapixels	4
Aspect ratio	1.42:1 (1 to √2 before rounding)
File size	11 MB as uncompressed 8-bit RGB; a JPEG or PNG is smaller
Paper size	594 × 841 mm (23.39 × 33.11 in)

Portrait

1684 × 2384 pixels

Landscape

2384 × 1684 pixels

With 3 mm bleed

1701 × 2401 pixels

Megapixels

Aspect ratio

1.42:1 (1 to √2 before rounding)

File size

11 MB as uncompressed 8-bit RGB; a JPEG or PNG is smaller

Paper size

594 × 841 mm (23.39 × 33.11 in)

The working

Pixels are inches multiplied by the resolution, and an inch is 25.4 mm.

Width: 594 mm ÷ 25.4 = 23.386 in; 23.386 in × 72 = 1,683.8, which rounds to 1684 pixels.
Height: 841 mm ÷ 25.4 = 33.11 in; 33.11 in × 72 = 2,383.9, which rounds to 2384 pixels.

Bleed is extra image past the trim line, so that a cut that lands slightly off still leaves ink to the edge. Print shops usually ask for 3 mm on every side of an A-series page, which makes the file 1701 × 2401 pixels.

Is your photo big enough?

To fill A1 at 72 DPI an image needs at least 1684 × 2384 pixels. Cropped to fill the sheet:

A 12 megapixel phone photo (4000 × 3000) gives 121 DPI: enough.
A 24 megapixel camera photo (6000 × 4000) gives 171 DPI: enough.
A 48 megapixel photo (8000 × 6000) gives 242 DPI: enough.

At 72 DPI the pixels of a print blend together from about 47.7 inches (121 cm) away. 72 DPI is the old screen convention: early Macintosh displays showed 72 pixels to the inch, matching the 72 points in an inch of type. Many image files still carry a 72 DPI tag for that reason.

A1 at other resolutions

Resolution	Pixels	With bleed	Megapixels	Uncompressed
72 DPI	1684 × 2384	1701 × 2401	4	11 MB
96 DPI	2245 × 3179	2268 × 3201	7.1	20 MB
100 DPI	2339 × 3311	2362 × 3335	7.7	22 MB
150 DPI	3508 × 4967	3543 × 5002	17	50 MB
200 DPI	4677 × 6622	4724 × 6669	31	89 MB
240 DPI	5613 × 7946	5669 × 8003	45	128 MB
300 DPI	7016 × 9933	7087 × 10004	70	199 MB
400 DPI	9354 × 13244	9449 × 13339	124	354 MB
600 DPI	14031 × 19866	14173 × 20008	279	797 MB
1200 DPI	28063 × 39732	28346 × 40016	1,115	3.12 GB

A1 is half of A0, a common size for posters, plans and flip charts. See A1 in pixels at every resolution or everything at 72 DPI.

A1 at 72 DPI is 1684 × 2384 pixels

The working

Is your photo big enough?

A1 at other resolutions

Other sizes at 72 DPI