Redacting a Spanish DNI vs a passport: what's different
Same principle, different layout — where the sensitive fields sit on each document.
Short answer
- A safe DNI copy is two images, not one — a redacted front with an untouched back defeats the point.
- Front: DNI number and date of birth. Back: the full three-line MRZ and the support number.
- NIE cards carry the same categories of sensitive fields and are redacted exactly the same way.
Most of our guides talk about passports because the risk and the fix are the same worldwide. If you’re in Spain, though, you’re just as likely to be asked for your DNI — and it’s laid out differently enough that it’s worth spelling out where the sensitive fields actually sit.
The passport: one page, everything together
A passport’s data page puts your photo, name, document number, dates and the machine-readable zone all in one place. Redacting it means covering several fields on a single image.
The DNI: split across front and back
A Spanish DNI spreads the same categories of data across two sides:
- Front: your photo, name, DNI number and date of birth.
- Back: the machine-readable zone (three lines, same ICAO 9303 standard as a passport) and, on the electronic DNIe, a separate support number (número de soporte) — sometimes requested on its own for online identity checks.
That means a “safe copy” of a DNI is really two images, not one, and both need attention — a redacted front with an untouched back defeats the point, since the back’s MRZ re-encodes the number and birth date anyway.
Where each field lives
| Field | On a passport | On a DNI / NIE | Action |
|---|---|---|---|
| Photo | Data page | Front | Keep |
| Name and surnames | Data page | Front | Keep |
| Document number | Data page | Front | Hide |
| Date of birth | Data page | Front | Hide |
| Signature | Data page | Front | Hide |
| Machine-readable zone | Two lines, foot of the data page | Three lines, back | Hide |
| Support number (número de soporte) | — | Back | Hide |
What to redact on each side
Front: the DNI number and date of birth (keep name and photo visible). Back: the entire machine-readable zone, and the support number unless the specific request needs it.
NIE cards follow the same rules
If you hold a NIE (Número de Identidad de Extranjero) rather than a DNI, the card layout and the same categories of sensitive fields apply — redact it exactly the same way.
Do both sides on your phone
Anonymize my ID redacts front and back the same way it handles a passport data page — photograph each side, cover the fields above, add a watermark, done entirely on-device. For the full method, see how to redact a passport or ID card; if you’re only sending one side because that’s all that’s been asked for, redact that side fully rather than assuming the other is safe by omission.
Frequently asked questions
Is a Spanish DNI redacted the same way as a passport?
The principle is identical — hide the document number, the machine-readable zone, date of birth and signature — but the layout differs. A passport puts everything on one data page; a DNI splits sensitive fields across the front and back.
Does the DNI have a machine-readable zone like a passport?
Yes. Modern Spanish DNIe cards carry a three-line MRZ on the back, in the same ICAO 9303 format used on passports worldwide, encoding much of the same data.
What's on the back of a DNI that isn't on a passport?
The MRZ and, on the DNIe, a support number (número de soporte) — a separate identifier from the DNI number itself, printed on the back, sometimes requested independently for online verification. It's sensitive for the same reasons and worth covering too.
I only have a NIE, not a DNI — does the same apply?
Yes. A NIE card follows a similar layout and carries the same categories of sensitive fields — number, MRZ, date of birth, signature — and should be redacted the same way.