ID Photos

30×40mm Photo: Pixel Size & Verified Uses

30×40mm photo: 354×472px at 300 DPI. Used for Korea alien registration card & China exit-entry documents. Preview free — HD download $1, 300-DPI print sheet $2

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Privacy note：Advanced smart enhancements show clear guidance before use. Please make sure you have permission to edit the photo.

Make Your ID Photo

40+ countries · 400+ China formats · Exact pixel output · crop-only mode for strict documents · background tools for eligible formats

What Is a 30×40mm Photo?

A 30×40mm photo — also written 3×4cm — is a small rectangular portrait size.

  • Physical size: 30×40mm (3×4cm, about 1.18×1.57 inches)
  • Pixels at 300 DPI: 354×472px
  • Pixels at 350 DPI: 413×551px — match the resolution your issuer states
  • 3:4 aspect ratio, portrait orientation

Common Uses

Verified examples from our spec database:

  • South Korea Alien Registration Card (외국인 등록증): 30×40mm, white background — reference data in our database; confirm current rules with Korean immigration
  • China exit-entry document photo (出入境证件): 354×472px = 30×40mm at 300 DPI, 20–80KB file, light-blue/white/grey background — per our China domestic spec database
  • Vietnam Citizen ID card (CCCD): 30×40mm — reference data; confirm with the issuing authority
  • Some China social security card variants: 30×40mm at 300 DPI — provincial rules differ

How to Make One Online

1

Choose the spec

Open the /id-photo tool and pick a 30×40mm preset (e.g. the China exit-entry spec) — or enter custom dimensions.

2

Upload a photo

Take a selfie against a plain wall or upload an existing shot. It is uploaded only when you choose AI processing; use the non-AI workflow for authorities that prohibit editing.

3

Preview free

AI centers the face, crops to the exact 3:4 ratio, and replaces the background. The preview costs nothing.

4

Download or print

Pay $1 for the exact-pixel HD file, or $2 for a 300-DPI print sheet with multiple copies on one page.

Background & Compliance Notes

  • Background: white is the norm (Korea alien card); China exit-entry photos also accept light blue or grey per our spec database
  • File-size limits can be strict (20–80KB for China exit-entry) — our tool tunes JPEG quality automatically
  • The issuer's official rules prevail — confirm background color, recency, and editing policy before submitting

Related keywords

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FAQ

What is a 30×40mm photo in pixels?
At 300 DPI it's 354×472 pixels; at 350 DPI it's 413×551 pixels. China's exit-entry spec uses 354×472px at 300 DPI.
Is 30×40mm the same as the Chinese 一寸 photo?
No. A 一寸 photo is 25×35mm (295×413px at 300 DPI) — smaller, with a different aspect ratio. Don't substitute one for the other.
Can I print a 30×40mm photo at home?
Yes. Our $2 print sheet lays out multiple copies on one 300-DPI page — print on photo paper and cut along the guides.