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Megapixel Calculator — Pixels to MP, Print Size & File Size

Convert pixel dimensions to megapixels, find maximum print size at any DPI, and compare popular cameras. Check if your camera resolution is enough for large prints.

✓ Free  ·  ✓ No upload  ·  ✓ Works offline in your browser

Megapixels

24.0 MP

6,000 × 4,000 pixels

Max Print at 300 DPI

20.0" × 13.3"

JPG Size (est.)

~11 MB

Megapixels Needed for Common Print Sizes

Print SizeMP at 300 DPIMP at 150 DPIMinimum Camera
4×6"2.2 MP0.5 MPAny smartphone
8×10"7.2 MP1.8 MP8 MP or more
11×14"13.9 MP3.5 MP14 MP or more
16×20"28.9 MP7.2 MP29 MP (Sony A7 IV)
20×30"54 MP13.5 MP54 MP (Sony A7R V)
24×36"77.8 MP19.5 MPMedium format

Frequently Asked Questions

How do I calculate megapixels from pixel dimensions?

Multiply width by height in pixels, then divide by 1,000,000. Example: 6000 × 4000 = 24,000,000 pixels ÷ 1,000,000 = 24 megapixels. Enter your dimensions above for instant results.

How many megapixels do I need for large prints?

At 300 DPI (professional print quality): 8×10" needs ~7 MP, 16×20" needs ~29 MP, 20×30" needs ~43 MP. At 150 DPI (acceptable for large prints viewed at distance): those same sizes need 4× fewer megapixels. Use the Print Size Check mode to test your specific image.

How many megapixels do I need for Instagram or web?

Social media and web use typically display images at 1080–2048 pixels wide, which is under 2 megapixels. Even a 12 MP phone camera is massively overpowered for web use. Megapixels only matter when you need to print large or crop heavily.

Does more megapixels always mean better photos?

No. Megapixels determine maximum resolution and print size, but image quality is primarily determined by sensor size, lens quality, and exposure. A 12 MP full-frame sensor will outperform a 48 MP small phone sensor in low light, dynamic range, and color depth.

How does megapixel count affect file size?

Uncompressed: each pixel takes ~3 bytes (RGB). A 24 MP image is 24,000,000 × 3 = 72 MB uncompressed. JPEG compression reduces this by ~6× (to ~12 MB). RAW files are 2–3× the JPEG size. The calculator estimates file sizes for your image dimensions.

What is DPI and how does it relate to megapixels?

DPI (dots per inch) is the print resolution — how many pixels are packed into each inch of paper. At 300 DPI, a 6000×4000 pixel image prints at 20" × 13.3". At 150 DPI, the same image prints at 40" × 26.7". Higher DPI = sharper but smaller print from the same megapixels.