---
id: KB-GL-005
url: https://app.codecontract.io/help/glossary/what-is-a-timestamp
idioma: en
categoria: glosario
subcategoria: firma
audiencia: usuario
nivel: intermedio
actualizado: 2026-08-13
tambienEn: [es]
relacionados: [KB-TZ-002, KB-GL-006, KB-GL-008]
citadoPor: [KB-SC-006, KB-SC-007, KB-TZ-008, KB-GL-015, KB-GL-006]
---

# What is a timestamp

_A date not set by whoever signed, which is why it counts._

**Responde a:** what is a timestamp · what a document timestamp is for · timestamping authority · how to prove a document's date

**Timestamp** — Certification, issued by an independent third party, that a specific document existed exactly as it stands at a given instant.

The value sits in "independent third party". If the date were set by whoever stores the document, you would have to trust them. Set by an authority outside both parties, the date stands on its own.

## What it certifies and what it does not

| Certifies | Does not certify |
| --- | --- |
| That this document existed on that date | That what it says is true |
| That it has not changed since | Who wrote it |
| That the time came from a third party | That it was lawful |

> [!NOTE]
> It is the difference between saying "I had this in March" and being able to prove it. In a dispute, the first is your word and the second admits no reply.

> [!WARNING]
> The seal covers the exact file. Reprint it or convert it and the file changes, so the seal no longer matches — correctly.

**Does it expire?**

The date certification does not expire. What ages are the algorithms, which is why long-retention documents get re-sealed.

**Can I check it myself?**

Yes, with no account, on the public verification page.

**Can something old be sealed?**

Yes, but the certified date is today's, not the original.

## Ejemplos

**A studio wants to prove a design was theirs before a client meeting.**

- Seals the design the day it is finished

→ When a similar product appears months later, the date does not rest on their word.

**Two parties argue over which of two versions came first.**

- Checks the timestamp on each

→ The order is set by a third party rather than by memory.

**A company saves a file and trusts the system's modified date.**

- Timestamps the document when it is finished

→ The date can no longer change when the file is copied.

**You want to prove a report existed before a meeting.**

- Timestamps the report the day it is closed

→ The proof does not rest on emails or diaries.

**A client doubts the annex they received is the one that was sealed.**

- Compares the annex's fingerprint with the registered one

→ The doubt is settled in seconds without argument.

**A document is sealed and afterwards a typo is corrected.**

- Seals the corrected version too

→ Both versions carry their own date and are distinguishable.