Supported document type
Detect tampered and deepfake China Resident ID (居民身份证)
The Resident Identity Card, 居民身份证, is the People's Republic of China's mandatory national ID for citizens, issued by the public security bureau under the Ministry of Public Security, and it is the identity anchor for banking, telecoms, and most official services. Its eighteen-character citizen number packs region, birth date, and sex into the digits and ends in a computed check character, so fabricated numbers fail their own arithmetic and mismatched edits show up against the printed fields.
API slug: china_resident_id
Last updated:
What a genuine Chinese resident ID contains
The citizen identity number has eighteen characters: the first six are a region code, the next eight are the birth date as year, month, and day, the next three are a sequence whose last digit is odd for men and even for women, and the final character is a check value that may be a digit or the letter X. The card prints name, sex, ethnicity, date of birth, address of permanent residence, photo, issuing authority, and a validity period.
Second-generation cards, issued since 2003, embed a chip that cannot be read from an image, and a scan often shows only one of the two faces. Cards in minority autonomous regions may print a second script beside Chinese, a trailing X is a legitimate check character, and older fifteen-digit numbers exist on legacy cards, so analysis separates normal variation from structural contradiction.
How Chinese resident ID forgeries are made
Check-character recomputation
The eighteenth character is computed from the first seventeen digits using the ISO 7064 MOD 11-2 scheme. A number that fails the computation was typed rather than issued, which makes it one of the cheapest structural checks available.
Embedded birth date and sex
Digits seven to fourteen carry the birth date and digit seventeen carries the sex. A card whose printed date of birth or sex disagrees with its own number was assembled from mismatched parts.
Validity against age
Validity terms depend on the holder's age at issuance, from five years for minors to a permanent term for older holders. A term that cannot fit the age implied by the birth date contradicts the issuing rules.
Region code coherence
The first six digits encode the registration region. A code that does not fit the issuing authority or the address province is an inconsistency forgers rarely reconcile.
Photo and text patching
Substituted portraits and edited name or address lines leave cut-line edges, resolution steps, and font passes. Uniform card printing makes localised anomalies stand out.
What TamperCheck checks on a Chinese resident ID
TamperCheck runs 200+ forensic checks across three layers and returns a risk score from 0 to 100 with plain-English findings tied to specific regions of the document. These three carry the most weight on this document class.
Portrait substitution and face-swap analysis
The document is isolated from whatever it was photographed on, then the portrait region is assessed against the card surface around it. A pasted or generated face rarely matches the substrate it was placed onto.
Date and validity consistency
Issue, expiry, and period dates are checked against one another and against the file's own creation metadata, which catches backdating and validity extension.
Reference and document number checks
Document, account, and reference numbers are checked for issuer format conformance and against every other place the same value appears on the page.
And many more checks
The three above are the layers that carry the most weight on a Chinese resident ID. Every upload runs the full suite of 200+ checks regardless of document class, spanning file structure and metadata, pixel-level forensics, font and text rendering, optical and print characteristics, provenance signals, AI-generation signatures, and many more checks.
Who verifies a Chinese resident ID, and why
Chinese banks, payment platforms, and cross-border onboarding teams. In each case the document is being used to unlock money, access, or a legal status, which is exactly what makes it worth forging.
How to verify a Chinese resident ID in 4 steps
Photograph every face
Capture the photo side and the issuing side flat at full resolution, so the number, birth date, and validity line survive close analysis.
Recompute the check character
Apply the MOD 11-2 computation to the first seventeen digits and compare with the eighteenth character, remembering that X is valid.
Cross-check the encoded fields
Compare digits seven to fourteen with the printed birth date, digit seventeen with the printed sex, and the validity term with the holder's age.
Run a forensic check on the file
The number carries the structural story, and the print carries the edit history. TamperCheck runs 200+ forensic checks including check-character recomputation and patch detection, returning a risk score from 0 to 100 with findings tied to specific regions of the image.
Frequently asked questions
What does the 18-character number on a Chinese ID encode?
A six-digit region code, an eight-digit birth date, a three-digit sequence whose parity marks sex, and a final check character. Because the encoding is deterministic, a card whose number contradicts its printed date of birth or sex was assembled rather than issued.
Is an X at the end of the ID number a mistake?
No. X stands for the check value ten and is a legitimate final character. A check character that fails the MOD 11-2 computation is the red flag, not the letter itself.
How long is a Chinese resident ID valid?
The term depends on age at issuance: five years under sixteen, ten years from sixteen to twenty-five, twenty years from twenty-six to forty-five, and permanent from forty-six. A term that does not fit the holder's age is a structural red flag.
How does TamperCheck verify a Chinese resident ID?
TamperCheck recomputes the check character, compares the encoded birth date and sex with the printed fields, tests the validity term against the holder's age, and inspects the portrait region for patching. Uploads run through a single REST endpoint, are processed ephemerally and not stored, and findings tie to specific regions.
TamperCheck analyses china resident id (居民身份证) uploads with a hybrid forensic and AI pipeline tuned for this document class. Upload endpoints accept PDF and common image formats; class is inferred automatically. See the API documentation for authentication, async jobs, and webhooks.