How 3.5 × 4.5 cm turns into 413 × 531 pixels
A photo file holds no centimetres, only pixels. To print at a physical size, those pixels are spread over the paper at a set density: the DPI, or dots per inch. Since one inch is 2.54 cm, the formula is pixels = cm ÷ 2.54 × DPI.
At 300 DPI that gives 3.5 ÷ 2.54 × 300 = 413.4, rounded to 413 px wide, and 4.5 ÷ 2.54 × 300 = 531.5, rounded to 531 px high. Change the DPI and the pixel count changes, but the printed size stays 3.5 × 4.5 cm:
| DPI | Pixels for 3.5 × 4.5 cm | Good for |
|---|---|---|
| 150 | 207 × 266 px | Uploads with a small KB limit |
| 200 | 276 × 354 px | Uploads and everyday prints |
| 300 | 413 × 531 px | Sharp photo prints (the preset) |
| 600 | 827 × 1063 px | Very detailed prints, at a much larger file size |
You will also see this size written as 35 × 45 mm, or with the height first as 4.5 × 3.5 cm. They all describe the same upright photo: 3.5 cm wide and 4.5 cm tall.
Where 3.5 × 4.5 cm photos are asked for
This is the most common “passport size” in South Asia and in much of the world. A few examples from official instructions:
- Indian passport forms on paper. The Passport Seva instruction booklet asks for a recent colour photo of 4.5 cm × 3.5 cm with a plain white background, pasted in the box on the form. It also says no photo is needed for applications made at a Passport Seva Kendra or Post Office Passport Seva Kendra, and that computer-printed photos are not accepted. (Passport Seva booklet)
- Pakistani embassy services. The Embassy of Pakistan in Bangkok, for example, lists two passport size photographs of 45 mm high × 35 mm wide for visa applications, and one 35 × 45 mm photo with a white background for a power of attorney. (MOFA)
- UK passports on paper. Printed photos must be 45 mm high by 35 mm wide, with the head 29–34 mm from crown to chin. (GOV.UK)
- Indian bank recruitment forms. IBPS scanning guidelines label the photograph 4.5 cm × 3.5 cm, but they also give upload dimensions in pixels and a KB range. More on that below.
Rules differ between offices and change between cycles, so treat these as examples and follow your own form.
When the form lists pixels as well as centimetres
Online forms check pixels and kilobytes, not centimetres. When instructions give both, the pixel numbers are what the upload screen actually tests. The IBPS guidelines for the 2025 PO/MT recruitment (CRP PO/MT-XV) are a clear example: the photo is described as 4.5 cm × 3.5 cm, yet the preferred dimensions are 200 × 230 pixels and the file must be 20–50 KB. (IBPS)
A 413 × 531 px file has more than four times the pixels of 200 × 230, so it is not what that form wants. For a case like this:
- Switch Resize by to Pixels and enter 200 × 230.
- Keep Crop to fill exact size. 200 × 230 is a little wider in shape than 3.5 × 4.5 cm, so slightly more is trimmed from the top and bottom. Check the preview.
- Turn on Limit file size and enter 50. The pixel size stays fixed and only the JPG quality is lowered.
- If the portal says the file is too small, turn the limit off and raise the quality slider to 100%: the file grows, the pixel size doesn't.
The opposite case is the UK online passport service. Its digital photo must be no smaller than 600 pixels wide by 750 tall, between 50 KB and 10 MB, and uncropped, because the service crops it for you. A 3.5 × 4.5 cm resize is the wrong file for that service: upload the original instead.
Resizing a photo is not the same as making a passport photo
This page changes the size and shape of a photo you already have. It doesn't look at what is in the picture: there's no face detection, it won't check that your head is the right height, and it doesn't touch the background. The crop is taken from the centre, so if you stand off to one side or were framed high, the result can cut off part of your head.
For an official passport or visa photo, use the Passport Photo Maker. You drag and zoom your photo under crown and chin guide lines set for each country, then download a digital file or a 4×6 in or A4 print sheet. The country pages explain the rules for India, Pakistan, the UK and the Schengen visa.
This resizer is the quicker choice when the photo is already well framed and you only need it at 3.5 × 4.5 cm: for an ID card, a college or job application, or a batch of staff photos that must all match.
Printing at exactly 3.5 × 4.5 cm
Because the DPI is written into the JPG, software that reads it places the photo at the right size. Before you print:
- In Microsoft Word, the inserted picture's size settings should read 4.5 cm high and 3.5 cm wide.
- On a home printer, set the scale to 100% (some apps call it Actual size) and switch off any fit-to-page option, which would blow the photo up to fill the paper.
- Measure one print with a ruler. If it's off, the printer or the app scaled it.
- For several copies on one sheet, the Passport Photo Maker lays out as many 35 × 45 mm photos as fit on 4×6 in or A4 paper, with cut guides.
Some offices are strict about print quality: the Indian passport booklet asks for clear, continuous-tone prints on good photo paper. For anything official, a studio or lab print is the safer route.
Getting a sharp result
- Start from the original photo. A camera-roll original has far more than 413 × 531 pixels, so the resize only shrinks it and stays crisp. A copy saved from a chat app or a screenshot has already lost detail.
- Leave room around your head when you take the picture, so the centre crop has something to trim on every side.
- Need a signature for the same form? The 140 × 60 px signature resizer is set up for bank recruitment forms.