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A Japanese passport online application needs more than a face photo — it also needs an image of your signature (自署, jisho). The photo spec is widely documented; the signature image is where a surprising number of applications stall.
Part of the reason: the signature you photograph is printed directly into your passport. Since there is no editing it afterwards, it is worth getting the spec and the technique right the first time.
There are two ways to supply the signature image, and the requirements differ. Confusing them is what produces a size rejection.
| Method | Format | Size | File size |
|---|---|---|---|
| Upload an image you prepared | jpg | 788 × 284 pixels | Under 200KB |
| Separate in-application upload | jpg / jpeg / bmp / png (RGB) | Not specified | 20KB – 2MB |
| Capture with the app camera | Automatic | Match the guide frame | Automatic |
Source: MOFA — Notes on face photos and signature images for online applications (verified August 2026)
Note that it is landscape (788×284px). The face photo is portrait (600×730px), so building the signature image with the same mental model gets the orientation backwards.
Leave headroom on file size
MOFA notes that even when a file is within the stated size range, compression applied during upload can push the result over the limit and trigger an error. Rather than aiming at the ceiling, leave yourself some margin.
You don't have to build an image file at all. You can photograph the signature directly in the MynaPortal application screen.
A guide frame appears on screen; you simply align your signature with the frame and press the capture button. Sizing and cropping are handled automatically, so pixel dimensions never come into it.
Unless you have a specific reason to do otherwise, this is the most reliable path. Building a 788×284px file yourself only matters if you want to use a prepared image.
Meeting the spec is not sufficient on its own — how you write it matters.
A thin pen and a small signature produce faint, broken strokes once digitised. Signing about one size larger than your habitual signature gives a noticeably cleaner result.
Shadows are the single most common failure on signature images. Bringing your face close to the paper puts your own body and hand between the light and the page.
Standing with a ceiling light behind you drops your shadow onto the page. Working near a window, with light arriving from the front or front-side, is much more forgiving.
Your signature is transferred to the passport
The captured signature image is printed in your passport. MynaPortal states directly: 「パスポートに記載される自署画像になりますので、内容をよく確認してください」 — this becomes the signature image recorded in your passport, so check it carefully. If you spot a mistake, retake it before submitting.
The signature image is requested together with the face photo, which has its own separate spec: 600 × 730 pixels, JPEG, under 600KB.
Face photo requirements and upload-error fixes are covered in Japan passport online photo upload and errors, including how to get from a phone shot to compliant data.
Turn one phone shot into compliant photo data
Automatic conversion to the passport online application format — 600×730px, under 600KB, JPEG.
Create Your PhotoNote
This article is based on MOFA and MynaPortal public information current as of August 2026. Specifications and procedures can change. Please verify on the MOFA guidance page before applying.
If you upload a file you prepared yourself: jpg format, 788 × 284 pixels, under 200KB. If you capture it with the MynaPortal app camera, it is sized automatically — just align your signature with the on-screen guide frame.
No. You can photograph it directly in the MynaPortal application screen. Align your signature with the guide frame and press the capture button. Uploading a prepared image file is an alternative, not a requirement.
Plain white paper with no ruled lines, signed in dark black or blue ink. Avoid paper with stains, folds, or show-through. Slightly thicker paper is safer.
Yes. The captured signature image appears in your passport. MynaPortal explicitly asks you to check it carefully before proceeding. If you want to redo it, do so before submitting.
Move the camera away from the paper and shoot from directly above in a bright spot. Leaning over the paper casts a shadow. Position yourself so light comes from the front or front-side rather than from behind you.
For a prepared signature image, jpg. On the separate in-application upload path, jpg, jpeg, bmp and png are accepted in RGB color mode, between 20KB and 2MB.