This tool validates two common Colombian identity numbers. The cédula de ciudadanía is the personal national ID — a plain serial with no public check digit, so only its format can be confirmed. The NIT (Número de Identificación Tributaria, the tax ID) does carry a modulo-11 verification digit defined by the DIAN, which this tool can compute and check. It is built for catching data-entry errors, and never contacts any registry.
How the cédula and NIT checks work
For a cédula, the tool confirms only that the number is plausibly formed: 6 to 10 numeric digits. There is no algorithm to prove a specific cédula is genuine.
For a NIT, it computes the verification digit (DV). Reading the base number right to left, each digit is multiplied by the DIAN weight series 3, 7, 13, 17, 19, 23, 29, 37, 41, 43, 47, 53, 59, 67, 71. The products are summed, then taken modulo 11:
- Remainder 0 or 1: DV = remainder
- Otherwise: DV = 11 − remainder
It then tells you the DV, or whether a DV you supplied matches.
Colombian document types overview
Colombia uses several identity documents depending on the person and purpose:
| Document | Abbreviation | Used by | Check digit? |
|---|---|---|---|
| Cédula de ciudadanía | CC | Colombian citizens aged 18+ | No |
| Tarjeta de identidad | TI | Colombians aged 7–17 | No |
| Cédula de extranjería | CE | Resident foreigners | No |
| Pasaporte | PA | Travel document | No (issuing country rules apply) |
| NIT | NIT | Businesses and self-employed individuals | Yes (DV, modulo-11) |
| NUIP | — | Newborn Colombians (since 1997) | No |
The NIT is the document most commonly validated programmatically because it appears on invoices, contracts, and tax filings (facturas electrónicas) and the DIAN check digit catches transposition errors in data entry.
The NIT algorithm step by step
The DIAN modulo-11 algorithm for a NIT base number works as follows:
- Write out the base digits right to left.
- Multiply each digit by the next weight in the series: 3, 7, 13, 17, 19, 23, 29, 37, 41, 43, 47, 53, 59, 67, 71.
- Sum all the products.
- Divide the sum by 11 and take the remainder.
- If the remainder is 0 or 1, that is the DV. If it is 2–10, the DV is 11 minus the remainder.
A correct NIT is written as base-DV, for example 900.373.115-3, with the base formatted in groups of three digits separated by dots.
Example
For the NIT base 900373115, applying the weights right to left:
| Digit (right→left) | Weight | Product |
|---|---|---|
| 5 | 3 | 15 |
| 1 | 7 | 7 |
| 1 | 13 | 13 |
| 3 | 17 | 51 |
| 7 | 19 | 133 |
| 3 | 23 | 69 |
| 0 | 29 | 0 |
| 0 | 37 | 0 |
| 9 | 41 | 369 |
| Sum | 657 |
657 mod 11 = 8, and since 8 is between 2 and 10, the DV is 11 − 8 = 3 — so
the full NIT is 900.373.115-3. A cédula like 1020304050 (10 digits) passes
the format check, but cannot be confirmed beyond that.
Every check runs locally in your browser — the number is never sent anywhere or verified against any registry.
Practical gotchas when handling Colombian IDs
- A person’s NIT is usually their cédula. For natural persons registered with the DIAN, the NIT base is the cédula number itself plus the computed DV. So the same digits can be a bare cédula in one system and a NIT-with-DV in another — store the document type alongside the number.
- Strip the formatting before validating. NITs appear as
900.373.115-3on invoices; the dots and dash are presentation only. Validate on the raw digits, but keep the DV separate from the base — appending it to the base and re-computing gives a different (wrong) result. - Don’t zero-pad cédulas. Older cédulas legitimately have 6–8 digits; padding them to 10 creates a different number. Store as text, never as an integer.
- A matching DV is not registration. The DIAN’s RUT registry is the only source that can confirm a NIT is actually assigned and active. The DV check filters typos; it cannot detect a fabricated-but-well-formed number.
A sensible validation order for forms
For invoice or onboarding flows the reliable order is: normalise (strip dots, dash, spaces) → detect type (DV present? length?) → format-check cédulas → recompute the DV for NITs → only then, if the business case requires it, query the RUT. Doing the cheap local checks first keeps registry lookups — which are rate-limited and slow — for numbers that are at least structurally credible.
Sources and references
- DIAN (Dirección de Impuestos y Aduanas Nacionales) — the tax authority that defines the NIT verification digit (DV) and hosts the RUT registry
- Registraduría Nacional del Estado Civil — the authority that issues the cédula de ciudadanía
Maintained by the Gera Tools editorial team. The DIAN modulo-11 weight series (3,7,13,17,19,23,29,37,41,43…) is the official NIT DV algorithm; the cédula has no public check digit, so only its format is verified. No registry is contacted. Last reviewed 2026-07-02.