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Megapixel Print Size Calculator

How big can you print a photo? Enter megapixels (or pick your camera) and see the largest sharp print at 300 DPI, plus exactly which standard frames it fills.

A vintage film camera and a modern smartphone side by side on a wooden desk with three printed photographs of varying sizes

1. How many megapixels?

MP

Or pick a camera

Aspect ratio

2. Largest print sizes

Max sharp print at 300 DPI:

13.3× 10

4,000 × 3,000 px source

At 200 DPI (compromise)20″ × 15
At 150 DPI (viewing distance)26.7″ × 20

3. Frame compatibility (300 DPI)

5×7"
300 DPI
8×10"
300 DPI
11×14"
~286 DPI
12×18"
~222 DPI
16×20"
~200 DPI
18×24"
~167 DPI
24×36"
~111 DPI

Megapixels → Print Size Quick Reference

Maximum sharp print sizes at 300 DPI for common camera megapixel counts. Assumes a 4:3 aspect ratio (most camera default).
Megapixels Pixel Dimensions Max @ 300 DPI Typical Source
1 MP1,155 × 8663.8″ × 2.9″AI image (1024 px)
4 MP2,309 × 1,7327.7″ × 5.8″AI image (2048 px)
8 MP3,265 × 2,44910.9″ × 8.2″Older smartphone
12 MP4,000 × 3,00013.3″ × 10.0″iPhone 12-14, GoPro
17 MP4,762 × 3,57115.9″ × 11.9″AI upscaled 4x
24 MP5,656 × 4,24218.9″ × 14.1″Entry DSLR / mirrorless
36 MP6,928 × 5,19623.1″ × 17.3″Pro DSLR (Nikon D810)
48 MP8,000 × 6,00026.7″ × 20.0″iPhone 15-16 Pro
78 MP10,200 × 7,64034.0″ × 25.5″Pro medium format
Vertical scale showing how camera megapixels map to maximum print size at 300 DPI from 2 MP (4x6 print) to 78 MP (24x36 poster)
From a 4×6 home print to a 24×36 statement poster — how megapixels limit your maximum print size at 300 DPI.

When you’d use this calculator

Megapixel-to-print-size translation comes up constantly in real seller workflows, especially when working with phone photos, AI-generated art, or stock photos with limited info about their dimensions. These are the four scenarios where I reach for it most:

  1. Deciding whether a phone photo can become a wall art listing. Customers regularly send "snap a photo of my dog and turn it into wall art" requests. A 12 MP iPhone photo can comfortably make 8×10 and 11×14 prints sharp at 300 DPI, but falls short for 16×20 and above. The calculator tells you in advance whether you need to upscale before promising the size.
  2. Sizing AI-generated art for print sale. Midjourney, DALL·E, and Stable Diffusion all default to small generations (1,024 px or 2,048 px square). At 1 MP an AI image only prints sharp at 3-4 inches — useless for wall art. The calculator confirms you need to upscale at least 4× before a 16×20 listing makes sense, and 8-10× before a 24×36.
  3. Validating a stock photo purchase before you commit. Most stock photo sites list pixel dimensions but not megapixels. Plug the dimensions in (or use the matching MP value) and confirm you’re buying enough resolution for the prints you plan to sell. A 6 MP stock photo at $30 is wasted money if you need 16×20 prints.
  4. Quoting custom-portrait commissions. If a buyer wants a 24×36 commissioned print but only has a 12 MP source photo, you need to either decline, redirect them to a smaller size, or include AI upscaling in the project plan. The calculator gives you a defensible answer in 5 seconds and saves an awkward conversation later.

Common megapixel mistakes

Megapixel math seems simple but trips people up in predictable ways. These five mistakes account for the bulk of "why does my print look bad?" support tickets I’ve seen.

1. Counting megapixels before cropping

A 24 MP photo cropped to 50% of its area is no longer a 24 MP photo — it’s 12 MP, with a third the print capacity. Always check the megapixel count of the final cropped file, not the original.

2. Confusing stored MP with displayed MP

Some smartphones (especially those with 48 MP or 50 MP sensors) actually save 12 MP files by default and only output at full resolution in a "Pro" or "RAW" mode. If your iPhone 15 Pro or Galaxy S24 photos are showing as 4,032×3,024 in your library, you’re only using a quarter of the sensor. Check your camera app's resolution setting.

3. Assuming AI upscalers add free megapixels forever

AI upscaling is excellent up to about 4-8× the original size. Beyond that, even the best models start to invent details that look unnatural at full resolution. A 1 MP AI image upscaled to 100 MP will look impressive at thumbnail size but show artifacts in print. Plan for a 4× max from each upscaling step.

4. Forgetting that aspect ratio changes the math

A 24 MP photo is roughly 6,000×4,000 pixels at 3:2, but only 5,656×4,242 at 4:3 and 4,899×4,899 if cropped square. The same megapixel count fills different print sizes depending on its aspect ratio. The calculator above lets you switch ratios so you can compare.

5. Treating megapixels as a quality guarantee

A 50 MP photo from a budget phone in low light can look worse printed than a 12 MP photo from a flagship in good light. Megapixels determine print size capacity, not image quality. Sharpness, focus, and color accuracy still matter most for the final print.

Need more megapixels? Ratio Ready upscales any image up to 4× or 10× with AI — covered in our AI upscaler, wall art converter, and poster maker.

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