Resize Image to 30×40 mm

30 × 40 mm is a compact ID photo size in the 3:4 shape of an upright phone photo. At 300 DPI it is 354 × 472 pixels, and nearly nothing is cropped from a portrait phone picture. Everything runs in your browser — nothing is uploaded. Need a smaller file instead? Compress or convert.

or drop images here — or press Ctrl + V to paste

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Width (px)

Height (px)

Unit

DPI

Keep aspect ratio (set one, the other follows)

Scale 50%

Aspect ratio

Width in pixels (optional)

Fit whole image inside instead of cropping to fill (result may be smaller than the preset)

Output format

Output quality 90

Position & zoom

Zoom 100%

Drag the preview to choose which part of the image is kept. The same framing is used for every image in the batch.

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resized

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new size

Added 0 files

Why choose 30×40 mm?

30×40 mm — that is 3×4 cm, 1.18×1.57 in — is the size asked for ID cards, passport-style photos and application forms. Saved at 300 DPI it is 354×472 pixels.

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354×472 px at 300 DPI

The pixel size is worked out for you, and the file is saved with 300 DPI so it prints at exactly 30×40 mm.

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Where it is used

30×40 mm is a common size for ID cards, passport-style photos and application forms. Check the requirements of the form or printer you are sending it to.

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36 per A4 sheet

With small gaps, 36 photos fit on one A4 page and 36 on US Letter — handy for printing several copies at home.

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3:4 portrait shape

The portrait 3:4 proportion decides the framing. Drag the preview so the subject sits where the rules expect it.

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About 26 KB–52 KB as JPG

At 300 DPI a 30×40 mm photo is usually 26 KB–52 KB. If a form limits the file size, pair it with the compressor.

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Same size, other units

30×40 mm equals 3×4 cm or 1.18×1.57 in. Enter whichever unit your instructions use — the result is identical.

30×40 mm at a glance

Size	30×40 mm = 3×4 cm, 1.18×1.57 in
Pixels at 300 DPI (print)	354×472
Pixels at 600 DPI (high quality)	709×945
Pixels at 200 DPI	236×315
Pixels at 150 DPI	177×236
Aspect ratio	portrait 3:4
Copies per A4 sheet	36
Copies per US Letter sheet	36
Copies per 4×6 in photo paper	8
Typical JPG at 300 DPI	26 KB–52 KB
Same and similar sizes	3×4 cm, 1.18×1.57 in, 1.38×1.38 in, 1.5×1.5 in

Resize a photo to 30×40 mm in 3 steps

Add your photo — a clear, well-lit original works best.
The size is already set to 30×40 mm at 300 DPI. Drag and zoom the preview to frame the face or subject.
Click Resize and download. Print it at 100% (“actual size”) so it comes out at 30×40 mm.

New to image resizing? Read the full resizing guide.

Square sizes

Same width and height — profile photos, icons, product shots:

8 × 8 10 × 10 16 × 16 28 × 28 32 × 32 40 × 40 50 × 50 64 × 64 96 × 96 98 × 98 100 × 100 112 × 112 120 × 120 128 × 128 144 × 144 150 × 150 180 × 180 184 × 184 192 × 192 200 × 200 240 × 240 250 × 250 256 × 256 300 × 300 320 × 320 350 × 350 360 × 360 400 × 400 450 × 450 480 × 480 500 × 500 512 × 512 600 × 600 640 × 640 700 × 700 800 × 800 840 × 840 900 × 900 1000 × 1000 1024 × 1024 1080 × 1080 1100 × 1100 1200 × 1200 1300 × 1300 1400 × 1400 1500 × 1500 1600 × 1600 1920 × 1920 2000 × 2000 2048 × 2048 2400 × 2400 2500 × 2500 3000 × 3000 4000 × 4000 5000 × 5000 6000 × 6000

Landscape sizes

Wider than tall — screens, banners, covers and thumbnails:

64 × 32 140 × 110 150 × 100 200 × 150 300 × 80 300 × 250 320 × 240 400 × 150 480 × 360 512 × 128 512 × 256 555 × 425 600 × 240 600 × 400 (3:2) 640 × 360 640 × 480 (4:3) 680 × 240 800 × 600 (4:3) 851 × 315 900 × 600 1000 × 500 1024 × 576 (16:9) 1080 × 566 1128 × 191 1200 × 628 1200 × 630 1200 × 675 (16:9) 1200 × 800 1200 × 900 1280 × 700 1280 × 720 (HD) 1366 × 768 1500 × 500 1500 × 1000 (3:2) 1600 × 900 1920 × 1080 (Full HD) 1920 × 1200 (16:10) 2048 × 1152 (2K) 2560 × 1440 (1440p) 2660 × 1140 (banner) 3000 × 1500 3440 × 1440 3840 × 2160 4080 × 3060

Portrait sizes

Taller than wide — passport photos, forms and phone screens:

Change the aspect ratio

Fit an image to a ratio without choosing pixels:

Any aspect ratio 16:9 4:3 3:2 1:1 4:5 5:4 3:4 2:3 9:16 21:9 5:2

Paper, print & photo sizes

Paper and photo sizes in mm, cm and inches, plus DPI tools:

A5 A4 A3 Letter Legal 4R (4 × 6 in) Postcard Stamp size Signature 2.5 × 2.5 cm 3 × 4 cm 3.3 × 4.8 cm 3.5 × 2.5 cm 3.5 × 3.5 cm 3.5 × 4.5 cm 3.5 × 5 cm 3.81 × 3.81 cm 4 × 3 cm 4 × 4 cm 4 × 5 cm 4 × 6 cm 4.5 × 3.5 cm 5 × 5 cm 5 × 7 cm 5.08 × 5.08 cm 25 × 25 mm 30 × 40 mm 32 × 26 mm 33 × 48 mm 35 × 35 mm 35 × 45 mm 35 × 50 mm 35 × 54 mm 36 × 36 mm 38.1 × 38.1 mm 40 × 50 mm 45 × 35 mm 45 × 38 mm 47 × 36 mm 50 × 50 mm 50 × 70 mm 50.8 × 50.8 mm 51 × 51 mm 52 × 40 mm 1.18 × 1.57 in 1.30 × 1.89 in 1.38 × 1.38 in 1.38 × 1.77 in 1.5 × 1.5 in 1.97 × 2.76 in 2 × 2 in 3 × 3 in 4 × 6 in 5 × 7 in 6 × 4 in 8 × 10 in 8.5 × 11 in Resize in pixels Resize in cm Resize in mm Resize in inches Resize by percentage 72 DPI converter 100 DPI converter 150 DPI converter 200 DPI converter 300 DPI converter 600 DPI converter

Resize for a platform

Ready-made sizes for social profiles and posts:

Resize tools

Batch resizing, DPI and crop tools:

Bulk image resizer Resize for printing Image DPI converter Image DPI checker Circle crop Square crop

300 or 600 DPI for a 30×40 mm photo?

At 300 DPI, 30×40 mm is 354 × 472 pixels. That is plenty for a sharp ID print. Some photo labs and card printers ask for 600 DPI (709 × 945 pixels) — switch the DPI box to 600 before resizing if yours does.

Why the shape is easy. Upright phone photos are 3:4, exactly the same shape as 30×40 mm, so resizing keeps the whole picture. Only check the face is large enough — at least two thirds of the height.

Printing a sheet. About twelve 30×40 mm photos fit on one 6×4 inch print — cheaper than printing them one by one.

Same size in cm: 3×4 cm. Slightly larger: 35×45 mm, 40×50 mm.

Similar print and photo sizes

Nearby print sizes, saved at 300 DPI so they print at the right size:

3.5 × 4.5 cm 3.3 × 4.8 cm 33 × 48 mm 3.5 × 5 cm 35 × 50 mm 3.5 × 3.5 cm 35 × 35 mm 4 × 5 cm

Frequently asked questions

Is 30×40 mm the same as 3×4 cm?

Yes. 30 mm is 3 cm and 40 mm is 4 cm — both are 354×472 pixels at 300 DPI.

How many photos of 30×40 mm fit on an A4 page?

About 36 on A4 and 36 on US Letter, leaving 5 mm margins and 3 mm between photos. On 4×6 inch photo paper you can fit 8.

What DPI should a 30×40 mm photo be?

300 DPI is the standard for photo prints and gives 354×472 pixels. Some offices accept 200 DPI (236×315); 600 DPI (709×945) is only needed for very high-quality printing.

What is 30×40 mm in other units?

30×40 mm is 3×4 cm, 1.18×1.57 in. Close sizes that are often confused with it: 3×4 cm, 1.18×1.57 in.

Why does my 30×40 mm print come out the wrong size?

Most printers scale images to “fit page” by default. Choose “actual size” or 100% in the print dialog, and the photo will print at exactly 30×40 mm.

How large is a 30×40 mm photo file?

Usually 26 KB–52 KB as a JPG at 300 DPI. If an online form allows less, reduce it with the compressor — the print size stays the same.

Are my images uploaded?

No. Resizing happens entirely in your browser. Nothing is transmitted or stored, and you can disconnect from the internet after the page loads and it still works.