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JPG to PDF 400 KB

400 KB is 409,600 bytes, and it is the cap most identity document uploads settle on. Two or three photos fit at a quality where the small print on a card stays readable. Build the PDF from the photos first, then compress it to the target and check the result.

JPG to PDF

The identity document case

Most 400 KB forms want the two sides of one card, or a passport page and a signature page. Two images share 409,600 bytes at about 200 KB each, which is enough to keep a document number, an expiry date and the fine print legible.

That legibility is the whole point. A form that cannot read the number will be rejected by a person, not by a size check, so the useful question is not whether the file fits but whether the smallest text on it survived.

Photograph it properly first

Fill the frame with the card. Photograph it flat on a plain surface with even light and no flash, because a flash on a laminated card produces a bright patch that hides exactly the text someone needs to read. Crop to the edges before you leave the phone.

Then the images to PDF tool puts the photos on pages with the original pixels, and the 400 KB compress target takes it down to the cap and checks the output.

Choosing the right cap

A 500 KB target gives each side another 50 KB if the form allows it, which is worth taking when the card has dense print. A 200 KB target is the tighter option, and at two images it leaves 100 KB per side, which is where a card number starts to soften.

Whichever you pick, open the result and zoom in on the smallest text before you upload it. That check takes ten seconds and it is the only one that matters.

Questions people ask

Is 400 KB enough for both sides of an ID card?
Yes, at about 200 KB per side. Card numbers, dates and fine print stay readable at that budget if the photos were taken flat and cropped. Zoom in on the smallest text on the result to be sure.
Should I use flash when photographing an ID document?
No. A flash on a laminated card creates a bright patch that hides the text underneath it. Even indirect light with no flash gives a flatter image, which is both more readable and smaller to store.
Why does my ID photo look soft after compression?
Because the target forced the image quality down. Check what the compress step reported. If it hit its quality floor, the cap was too tight for the photos, and cropping harder before you start is the fix.
Can I put two photos on one PDF page?
Not in this flow. The images tool writes one image per page, which keeps each one at full page size and therefore readable. Two cards on one page halves the pixels available to each.

Do it now

The tool runs in this browser. Your file never leaves the machine, and the result is checked before you download it.

JPG to PDF

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