4x6" Photo Print Quality Checker
The classic 4 × 6 inch (102 × 152 mm) photo print requires a resolution of 1200 × 1800 pixels at 300 DPI for lab-quality sharpness.
At 300 DPI (Gallery Sharp): Minimum 1200 × 1800 pixels.
At 150 DPI (Poster Viewing): Minimum 600 × 900 pixels.
4×6" Print Guide
Everything you need to print 4x6" Photo sharp
The 4 × 6 inch print (10 × 15 cm) is the classic photo print from drugstores, photo kiosks and online labs, and the most common postcard size in the US.
Its 2:3 shape matches most digital cameras exactly, so camera photos print without cropping. Phone photos are usually 4:3, a little squarer, so a strip is trimmed from the long side.
At 300 DPI a 4 × 6 needs only 1200 × 1800 pixels, about 2.2 megapixels, so almost any original photo is plenty. Problems come from copies: images saved from social media or sent through messaging apps are often much smaller. A 1080 × 1350 Instagram image reaches about 225 DPI at 4 × 6: fine for a snapshot, but not lab-sharp.
4×6" at a glance
| Size | 101.6 × 152.4 mm · 10.16 × 15.24 cm · 4 × 6 in |
|---|---|
| Shape (aspect ratio) | 2 : 3 |
| Common uses | Standard family photos, postcards, greeting cards, photo albums. |
Pixels needed for 4×6"
| Resolution | Pixels (width × height) | Megapixels | Best for |
|---|---|---|---|
| 300 DPI | 1200 × 1800 | 2.2 MP | Close up (photos, cards, documents) |
| 240 DPI | 960 × 1440 | 1.4 MP | Framed and wall prints |
| 150 DPI | 600 × 900 | 0.5 MP | Posters viewed from a distance |
Pixel sizes are for portrait. For landscape, swap width and height.
Tips for printing at 4×6"
- Choose the original file. If a print looks soft, the photo was probably shrunk when it was shared. Ask for the original or export it from your photo library at full size.
- Check what gets cropped. When printing 4:3 phone photos at 4 × 6, a slice of the image is trimmed. Many print services show a preview; check that heads and edges aren’t cut off.
- Borderless prints are trimmed slightly. Labs often enlarge the image a touch to avoid white edges, so keep important detail away from the very edge.
4×6" questions
How many pixels do I need for a 4 × 6 print?
1200 × 1800 pixels at 300 DPI. Most photo labs accept 900 × 1350 (225 DPI) or even less, but 1200 × 1800 gives the sharpest result.
Why does my phone photo get cropped at 4 × 6?
Phone cameras usually take 4:3 photos, while 4 × 6 is 2:3. To fill the print, part of the longer side has to be trimmed. Choose “fit” instead of “fill” if you would rather have white borders.
Can I print a screenshot at 4 × 6?
Often yes: modern phone screenshots are well over 1800 pixels tall. They are a much taller shape than 4 × 6, though, so expect heavy cropping or wide borders.
Simple Process
How PrintCheck Works
Three quick steps to ensure your physical prints never come out blurry or pixelated.
Input Target Dimensions
Specify the physical width and height in millimeters (mm) along with your required DPI (300 DPI fine art or custom DPI).
Upload Your Image
Select your image file. We read its pixel size and format, then delete it straight away. Your image is never kept.
Get 3-Tier Results
Instantly view whether your image passes, qualifies for AI upscaling, or requires a higher-resolution file.
Built For Print Shops & Designers
Everything You Need for Quality Control
Exact Pixel Formula
Automates (mm / 25.4) * DPI calculation instantly for any custom physical size.
Privacy-First Processing
Your image is only held while it is being checked, then deleted. We never keep, share or look at your images.
Smart AI Upscale Detection
Detects images that can be saved using modern AI upscaling up to 4× enlargement.
Standard Print Sizes & Pixel Resolution
Reference chart of required pixel dimensions for standard photo, poster, and paper formats.
Pixels = Inches × Target DPI
Example for 8×10" at 300 DPI: (8 × 300) = 2400 px width, (10 × 300) = 3000 px height.
Pixels = (Millimeters ÷ 25.4) × Target DPI
Example for A4 (210×297 mm) at 300 DPI: (210 ÷ 25.4 × 300) = 2480 px, (297 ÷ 25.4 × 300) = 3508 px.
| Print Format | Inches | Metric (mm) | 300 DPI (Gallery Sharp) | 150 DPI (Poster Standard) | Instant Check |
|---|---|---|---|---|---|
| A4 Paper (ISO Standard) | 8.27 × 11.69" | 210.0 × 297.0 mm | 2480 × 3508 px | 1240 × 1754 px | Check A4 |
| A3 Poster (ISO Standard) | 11.69 × 16.54" | 297.0 × 420.0 mm | 3508 × 4961 px | 1754 × 2480 px | Check A3 |
| A5 Booklet (ISO Standard) | 5.83 × 8.27" | 148.0 × 210.0 mm | 1748 × 2480 px | 874 × 1240 px | Check A5 |
| 4x6" Photo (US Photo) | 4.0 × 6.0" | 101.6 × 152.4 mm | 1200 × 1800 px | 600 × 900 px | Check 4×6" |
| 5x7" Photo (US Photo) | 5.0 × 7.0" | 127.0 × 177.8 mm | 1500 × 2100 px | 750 × 1050 px | Check 5×7" |
| 8x10" Print (US Photo & Art) | 8.0 × 10.0" | 203.2 × 254.0 mm | 2400 × 3000 px | 1200 × 1500 px | Check 8×10" |
| 11x14" Print (US Wall Art) | 11.0 × 14.0" | 279.4 × 355.6 mm | 3300 × 4200 px | 1650 × 2100 px | Check 11×14" |
| 12x18" Poster (Posters) | 12.0 × 18.0" | 304.8 × 457.2 mm | 3600 × 5400 px | 1800 × 2700 px | Check 12×18" |
| 18x24" Poster (Posters) | 18.0 × 24.0" | 457.2 × 609.6 mm | 5400 × 7200 px | 2700 × 3600 px | Check 18×24" |
| 24x36" Poster (Posters) | 24.0 × 36.0" | 609.6 × 914.4 mm | 7200 × 10800 px | 3600 × 5400 px | Check 24×36" |
Answers To Common Questions
Frequently Asked Questions
Print Guides
Learn how to get sharp prints
How to Check an Image’s Resolution on Windows, Mac, iPhone and Android
Step-by-step for every device, which number to look at, and which one to ignore.
How to Print AI Art Sharp: Sizes, Upscaling and Common Problems
How far a 1024 px image goes, the upscale factor for popular sizes, and what to fix before printing.
Print-on-Demand Image Requirements: A Guide for Gelato, Printful and Printify Sellers
Resolution, templates, transparency and colour: how to prepare designs that print well on shirts, mugs and wall art.
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