Exactly 500 x 653 Pixels
The strictest pixel rule of any country on this site.
The Finnish police photo guide states that an electronically submitted photo must measure exactly 500 x 653 pixels — "Yhdenkään pikselin poikkeamia ei hyväksytä", a deviation of even one pixel is not accepted. Most authorities publish a minimum and let you exceed it; Finland publishes a single number.
That is why this tool renders 36 x 47mm at 353 dpi rather than a round 300 or 600. Those figures land on 500 x 653 pixels exactly, so one file satisfies both the print measurement and the pixel rule.
The file must be JPEG — the guide explicitly excludes JPEG2000 — and stay under 250KB.