Unix Timestamp Converter
This tool helps you convert Unix timestamps (epoch time) into human-readable date formats and convert dates back into timestamps. It is widely used by developers, DevOps engineers, and system administrators.
What Is a Unix Timestamp?
A Unix timestamp (also called epoch time) represents the number of seconds that have elapsed since January 1, 1970 (00:00:00 UTC).
It provides a simple, timezone-independent way to represent time, which is why it is heavily used in operating systems, databases, APIs, and distributed systems.
Why Unix Timestamps Are Used
Unix timestamps avoid many common problems associated with date and time handling, such as timezone differences and locale-specific formats.
- Easy to store as a number
- Easy to compare and sort
- Consistent across systems
- Widely supported in programming languages
Common Real-World Use Cases
- API request and response timestamps
- Log files and audit trails
- JWT token expiration (
exp) - Database record creation times
- Monitoring and alerting systems
Seconds vs Milliseconds (Very Important)
One of the most common mistakes developers make is confusing seconds and milliseconds.
- Unix timestamp (seconds):
1700000000 - Unix timestamp (milliseconds):
1700000000000
JavaScript and many frontend systems use milliseconds, while backend systems often use seconds. Always verify which unit your system expects.
Time Zones and UTC
Unix timestamps are always based on UTC. They do not store timezone information.
When converting a timestamp to a human-readable date, the displayed time depends on whether it is rendered in UTC or converted to a local timezone.
Date → Timestamp Conversion
When converting a date to a timestamp, the date must be in a valid ISO-8601 format such as:
2026-01-25T12:30:00Z
ISO format ensures clarity and avoids ambiguity across systems.
Advantages of Unix Timestamps
- Compact numeric representation
- No timezone ambiguity
- Efficient for storage and indexing
- Ideal for distributed systems
Limitations and Pitfalls
- Not human-readable
- Easy to confuse seconds vs milliseconds
- Does not store timezone context
For user-facing applications, timestamps are usually converted into formatted dates before display.
Unix Timestamp in Programming Languages
- Python:
time.time() - JavaScript:
Date.now() - Linux:
date +%s - Databases:
UNIX_TIMESTAMP()
Security and Audit Logs
Unix timestamps are widely used in security logs, audit trails, and compliance systems because they are precise and tamper-resistant when combined with proper logging controls.
Best Practices
- Always document whether timestamps are in seconds or milliseconds
- Store timestamps in UTC
- Convert to local time only for display
- Validate input formats strictly
Who Should Use This Tool?
- Backend and API developers
- DevOps and SRE engineers
- Security and compliance teams
- Students learning systems programming
If you work with logs, APIs, authentication tokens, or distributed systems, this Unix timestamp converter can save time and prevent errors.