Enter the file size, width, height, DPI, and color depth into the calculator to determine the missing variable.

DPI to MB Calculator

Use the mode that matches what people usually want: estimate file size for printing, find effective DPI from pixels, or find the max DPI allowed by a file size limit.

This version is built around print-size, pixel-size, and file-size-limit use cases instead of a generic 5-variable solver.
Print Size → Estimated File Size
Pixels → Effective DPI
File Size Limit → Max DPI
Print size
Inches
Centimeters
Millimeters
4 × 6
5 × 7
8 × 10
Letter
A4
A3
Resolution and format
RGB
Grayscale
CMYK
RGB is a good default for most digital images.
JPEG High
JPEG Medium
PNG
PDF
TIFF or RAW
Pixel dimensions
Planned print size
Inches
Centimeters
Millimeters
4 × 6
5 × 7
8 × 10
Letter
A4
A3
File size limit
KB
MB
GB
Planned print size
Inches
Centimeters
Millimeters
4 × 6
5 × 7
8 × 10
Letter
A4
A3
Color mode and estimated format
RGB
Grayscale
CMYK
JPEG High
JPEG Medium
PNG
PDF
TIFF or RAW

Results

File size from DPI is always an estimate unless you also know the image dimensions and how the file is actually saved. JPEG, PNG, PDF, and TIFF can vary a lot.

Related Calculators

DPI to File Size Formula

The following formula is used to calculate the file size for a given width, height, DPI, and color depth. 

FS = (W * DPI) * (H * DPI) * CD / 8

Variables:

  • FS is the file size in bytes
  • W is the width in inches
  • H is the height in inches
  • DPI is the dots per inch
  • CD is the color depth in bits per pixel

To calculate the file size, multiply the width by the DPI, then multiply the result by the height and the DPI again. Multiply this result by the color depth and divide by 8 to convert bits to bytes.

DPI to File Size Conversion Table (US Letter 8.5×11 in, 24-bit RGB)
Resolution (dpi) File Size (MB)
721.39
962.47
1002.68
1506.02
20010.70
24015.41
25016.72
30024.08
35032.77
40042.80
45054.17
50066.88
60096.30
720138.68
800171.20
900216.68
1000267.51
1200385.21
1440554.70
24001540.83
Assumes uncompressed 24-bit RGB (3 bytes/pixel) at US Letter size (8.5×11 in). 1 MB = 1,048,576 bytes. File size scales with dpi².

What is DPI?

DPI stands for Dots Per Inch and is a measure of the resolution of a printed or digital image. It indicates the number of individual dots that can be placed within a linear inch. Higher DPI values mean more detail and sharper images, while lower DPI values result in less detail and blurrier images. DPI is commonly used in printing and scanning to ensure that images are reproduced with the desired clarity and detail.

How to Calculate File Size from DPI?

The following steps outline how to calculate the file size from DPI.

  1. First, determine the width of the image in inches (W).
  2. Next, determine the height of the image in inches (H).
  3. Next, determine the DPI (dots per inch) of the image.
  4. Next, determine the color depth in bits per pixel (CD).
  5. Finally, calculate the file size using the formula FS = (W * DPI) * (H * DPI) * CD / 8.
  6. After inserting the values and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

Width (W) = 8 inches

Height (H) = 10 inches

DPI = 300

Color Depth (CD) = 24 bits per pixel