Unix Timestamp Calculator
Epoch time conversion tool
Timestamp → Date
Date → Timestamp
Current Time Across Timezones
Quick Tips
Unix Epoch
Unix time starts at January 1, 1970 00:00:00 UTC
Seconds vs Milliseconds
Unix timestamps are in seconds. JavaScript uses milliseconds
Timezone Aware
Unix timestamps are always UTC. Convert to local time for display
Programming
Most languages have built-in functions for timestamp conversion
Batch Timestamp Converter
Enter multiple Unix timestamps (one per line) to convert them all at once
Batch Date Converter
Enter multiple dates (ISO format, one per line) to convert them to timestamps
Common Unix Timestamps
Important dates and their Unix timestamps for reference
| Date | Timestamp | Description |
|---|
Time Unit Conversions
Unix timestamp equivalents for common time units
| Time Unit | Seconds | Minutes | Hours |
|---|---|---|---|
| 1 Minute | 60 | 1 | 0.0167 |
| 1 Hour | 3,600 | 60 | 1 |
| 1 Day | 86,400 | 1,440 | 24 |
| 1 Week | 604,800 | 10,080 | 168 |
| 1 Month (30 days) | 2,592,000 | 43,200 | 720 |
| 1 Year (365 days) | 31,536,000 | 525,600 | 8,760 |
Understanding Unix Timestamps
What is Unix Timestamp?
Unix timestamp (also called Epoch time or POSIX time) is a system for describing a point in time. It's defined as the number of seconds that have elapsed since 00:00:00 UTC on Thursday, 1 January 1970, minus leap seconds.
The Unix Epoch
The Unix Epoch is the reference point for Unix time:
- Date: January 1, 1970
- Time: 00:00:00 UTC
- Timestamp: 0
- Day of week: Thursday
How It Works
Unix timestamps count the seconds since the epoch:
- Timestamp 0: Jan 1, 1970 00:00:00 UTC
- Timestamp 86400: Jan 2, 1970 00:00:00 UTC (one day later)
- Timestamp 1000000000: Sep 9, 2001 01:46:40 UTC
- Current: ~1.7 billion seconds since epoch
Programming Examples
How to work with timestamps in different languages:
- JavaScript:
Date.now()(milliseconds) orMath.floor(Date.now() / 1000)(seconds) - Python:
int(time.time()) - PHP:
time() - Java:
System.currentTimeMillis() / 1000 - C/C++:
time(NULL)
Year 2038 Problem
The Year 2038 problem (Y2038) is a bug that will affect systems using 32-bit signed integers for Unix timestamps:
- Issue: 32-bit signed integer overflows on January 19, 2038 at 03:14:07 UTC
- Timestamp: 2,147,483,647 (maximum 32-bit signed int)
- Solution: Use 64-bit integers for timestamps
- Impact: Most modern systems already use 64-bit, but legacy systems may be affected
Timezone Handling
Important considerations for timezones:
- Unix timestamps are always UTC: They don't include timezone information
- Display conversion: Convert to local time when displaying to users
- Storage: Store as UTC timestamp, convert on display
- DST: Be aware of Daylight Saving Time changes
Best Practices
- Store in UTC: Always store timestamps in UTC
- Use 64-bit integers: Avoid Y2038 problem
- Convert on display: Convert to user's local timezone when displaying
- Be explicit: Always specify timezone when working with dates
- Use ISO 8601: For human-readable dates, use ISO 8601 format
Developer Tips
Database Storage
Store timestamps as integers or TIMESTAMP type in databases
API Communication
Use Unix timestamps in APIs for unambiguous time representation
Time Synchronization
Use NTP to keep server clocks synchronized
Debugging
Always check if timestamps are in seconds or milliseconds
Understanding Unix Timestamps
Unix timestamps (also known as Epoch time or POSIX time) are a system for representing points in time as the number of seconds that have elapsed since January 1, 1970, at 00:00:00 UTC. This simple, universal format is widely used in computing for logging, scheduling, and data exchange.
Key Concepts
Understanding these key concepts about Unix timestamps:
- Unix Epoch: January 1, 1970 00:00:00 UTC (timestamp 0)
- Always UTC: Unix timestamps don't include timezone information
- Seconds-based: Count seconds since epoch (JavaScript uses milliseconds)
- Universal: Same timestamp worldwide, regardless of local timezone
- Monotonic: Always increases (except for leap second adjustments)
Common Use Cases
Unix timestamps are used in many applications:
- Logging: Timestamp log entries with precise timing
- Databases: Store creation/modification times
- APIs: Exchange time data between systems
- File systems: Track file modification times
- Caching: Set expiration times for cached data
- Scheduling: Schedule tasks and cron jobs
Programming Examples
Working with timestamps in popular programming languages:
- JavaScript:
Math.floor(Date.now() / 1000) - Python:
int(time.time()) - PHP:
time() - Java:
System.currentTimeMillis() / 1000 - C/C++:
time(NULL) - Ruby:
Time.now.to_i
Using This Calculator
Follow these steps:
- View Current Time: See the current Unix timestamp updating in real-time
- Timestamp to Date: Enter a Unix timestamp to see the human-readable date
- Date to Timestamp: Select a date and time to get the Unix timestamp
- Timezone Support: Convert between different timezones
- Batch Convert: Convert multiple timestamps at once
- Reference: Check common timestamps and time unit conversions
- Learn: Read the Guide tab to understand Unix time concepts
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