Reconstruct

Reconstructs possible NRIC numbers from partial known information. Useful for forensic or administrative recovery scenarios.

GET /nric/reconstruct

Parameters

Parameter	Required	Description
last	Yes	The last N characters of the NRIC (trailing digits + checksum letter), e.g. 567D
year	Yes	4-digit year of birth, e.g. 1990
citizenship	Yes	Citizenship status: S (Singaporean), P (Permanent Resident), or F (Foreigner)
born_sg	Yes	Whether born in Singapore: Y or N
month	No	3-letter birth month (e.g. Jan, Feb). Narrows results using SingStat birth data (Singapore-born citizens/PRs only)

Example

curl "https://api.uwuapps.org/nric/reconstruct?last=567D&year=1990&citizenship=S&born_sg=Y"

Response

{
  "count": 3,
  "truncated": false,
  "nrics": [
    "S9012567D",
    "S9034567D",
    "S9056567D"
  ]
}

Response fields

Field	Description
count	Total number of matching NRICs found
truncated	true if the result was capped at 1000 entries
nrics	Array of valid matching NRIC strings (max 1000)

How it works

1. The prefix (S, T, F, or G) is determined from citizenship and year.

2. The first 2 digits of the NRIC body are derived from the last 2 digits of year.

3. The 3rd digit indicates birth location: 0–5 for Singapore-born, 5–9 for foreign-born.

4. All valid combinations of the remaining unknown digits are tried.

5. Only combinations that produce a valid NRIC checksum are returned.

6. If month is provided, results are further filtered using SingStat birth registration data.

Notes

• A minimum of 1 character (the checksum letter) must be provided in last.

• Results are capped at 1000 to prevent excessively large payloads.

• The month filter is best-effort; if SingStat's API is unreachable, it is skipped and all matches are returned.