Resize Image in Millimeter: Precise Photo Tool
Converting digital pixels to physical millimeters (mm) is essential for official documents, badges, and engineering prints. Our Online Image MM Resizer makes it easy to set exact dimensions like 35x45mm or 50x50mm while automatically handling the DPI calculations for you.
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Why Resize in Millimeters? Accuracy Matters
Most official requirements for visas, passports, and driving licenses are specified in millimeters, not pixels. For example, a standard Schengen visa photo must be exactly 35mm x 45mm.
Simply cropping an image isn't enough. You need to ensure the image has the correct resolution (DPI) so that 35mm on screen equals 35mm on paper. Our tool performs the conversion: Pixels = (MM / 25.4) * DPI, ensuring your application doesn't get rejected due to incorrect sizing.
Why Choose This Batch MM Resizer?
Exact MM Precision
Input precise values like 35.0 mm or 51.0 mm. Perfect for meeting strict government or printing specifications.
DPI Control (300 Standard)
We default to 300 DPI (Dots Per Inch), the global standard for high-quality printing, ensuring your photos are sharp and clear.
Bulk Processing
Need to resize 20 staff photos for ID badges? Process them all at once to 40x60mm and download a ZIP file instantly.
Compress to Size
Many online forms limit uploads to "under 200KB". Our tool allows you to set a target file size limit while maintaining the correct millimeter dimensions.
How to Resize Images in MM Online
- Upload Images: Drag and drop your JPG, PNG, or HEIC files into the upload area.
- Set Dimensions (MM): In the "Physical Dimensions" panel, enter your required Width and Height in millimeters (e.g., 35 and 45).
- Check DPI: Ensure DPI is set to 300 for printing. Use 72 only for web-only usage.
- Export Settings: Choose JPG for photos. If you have a file size limit (e.g., max 100KB), check "Compress to Specific Size" and enter the value.
- Apply & Download: Click "APPLY SETTINGS TO ALL" to resize your batch, then download the ZIP file.
Common Photo Sizes in Millimeters (Cheat Sheet)
| Document Type | Size in MM (WxH) | Region / Usage |
|---|---|---|
| Standard Passport / Visa | 35 x 45 mm | UK, EU (Schengen), Australia, NZ |
| US Visa / India Visa | 51 x 51 mm | USA, India (2x2 inches) |
| China Visa | 33 x 48 mm | China |
| Canadian Visa | 35 x 45 mm | Canada (Back of photo size differ) |
| Credit Card Size | 85.6 x 54 mm | Standard ID-1 Cards |
| A4 Paper | 210 x 297 mm | Standard Document |
If yor're looking for a pro Passport & Visa Photo Maker, check out our Passport & Visa Photo Maker
Frequently Asked Questions (FAQ)
Q: How do I convert pixels to mm?
The conversion depends on resolution (DPI). At 300 DPI, the formula is: MM = (Pixels / 300) * 25.4. For example, a 600px wide image at 300 DPI is roughly 50.8mm wide.
Q: Is 300 DPI mandatory for passport photos?
Yes, almost all government agencies require a minimum of 300 DPI (or PPI) to ensure the photo features are clearly visible when printed or scanned. Lower resolutions (like 72 DPI) will result in rejection.
Q: Will this tool crop my image?
Our tool resizes the entire image. If you change the aspect ratio (e.g., turning a square photo into a rectangle), the image may stretch if you unlock the aspect ratio. For passport photos, we recommend cropping the face to the correct ratio first, then using this tool to resize to the specific MM.