What Is a Timestamp Converter?
A timestamp converter translates between Unix timestamps (seconds since January 1, 1970) and human-readable dates. Unix timestamps are the universal language of time in programming — every database, API, and logging system uses them because they're timezone-independent, sortable, and unambiguous.
Common Timestamp Formats
Unix (seconds) — 1700000000. The standard. Milliseconds — 1700000000000. Used by JavaScript and Java. ISO 8601 — 2023-11-14T10:13:20Z. The human-readable standard for APIs. RFC 2822 — Tue, 14 Nov 2023 10:13:20 +0000. Used in email headers and HTTP.
How to Use This Timestamp Converter
- Enter a Unix timestamp — Paste a Unix timestamp (seconds since January 1, 1970) to convert it to a human-readable date.
- Or enter a date — Select a date and time from the picker to convert it to a Unix timestamp.
- Choose your timezone — Select the timezone for the human-readable output — UTC, your local timezone, or any other zone.
- Copy the result — Grab the converted timestamp or formatted date string for your application.
When you need to know not just what a timestamp means but when a recurring job will next fire from it, the Cron Next Fire Times tool previews the next 10 firings of a cron expression in your chosen timezone.
To convert two human-readable dates into an exact years-months-days span instead of raw seconds, the Age Calculator runs the full YMD walk and includes a secondary date-difference tab.
For SLA windows or contract deadlines that need to skip weekends and holidays, the Business Day Adder walks a date forward or backward by N working days across bundled US, UK, CA, and AU calendars.
Tips and Best Practices
- → Unix timestamps are in seconds. JavaScript uses milliseconds (13 digits), but Unix timestamps are in seconds (10 digits). Divide JavaScript timestamps by 1000 or multiply Unix timestamps by 1000 when converting between them.
- → Store dates as UTC. Always store timestamps in UTC on the server and convert to local time on the client. This prevents timezone-related bugs and ensures consistency across users.
- → Use ISO 8601 for APIs. The format
2026-04-15T14:30:00Z is the international standard for date interchange. Use it in APIs, logs, and data storage.
- → Be aware of the Year 2038 problem. 32-bit Unix timestamps overflow on January 19, 2038. Modern systems use 64-bit timestamps, but legacy systems may need migration.
Frequently Asked Questions
What is a Unix timestamp?
Seconds since January 1, 1970 00:00:00 UTC (the epoch). A universal, timezone-independent time representation. Example: 1700000000 = November 14, 2023.
How do I convert a timestamp?
Use this tool, or in code: JavaScript new Date(ts * 1000), Python datetime.fromtimestamp(ts). This tool shows multiple formats instantly.
What is the Year 2038 problem?
32-bit signed integers overflow on January 19, 2038. Most modern systems use 64-bit integers, extending the range to billions of years.
What is a Unix timestamp?+
A Unix timestamp (also called epoch time or POSIX time) is the number of seconds that have elapsed since January 1, 1970, 00:00:00 UTC. It provides a universal, timezone-independent way to represent a specific moment in time. For example, 1713192000 represents April 15, 2024.
What is the difference between Unix time and ISO 8601?+
Unix timestamps are numeric (1713192000) — compact and timezone-independent. ISO 8601 is string-formatted (2024-04-15T14:00:00Z) — human-readable with explicit timezone info. Unix timestamps are better for storage and computation; ISO 8601 is better for APIs, logs, and display.
How do I get the current Unix timestamp?+
In JavaScript: Math.floor(Date.now() / 1000). In Python: import time; int(time.time()). In a terminal: date +%s. In SQL: UNIX_TIMESTAMP() (MySQL) or EXTRACT(EPOCH FROM NOW()) (PostgreSQL).
How do I convert a timestamp to a date?+
Use this tool — paste a Unix timestamp and instantly see the corresponding date and time in multiple formats. In JavaScript, use new Date(timestamp * 1000) (JS uses milliseconds). In Python, use datetime.fromtimestamp(timestamp).
How do I handle timestamps with milliseconds versus seconds?+
Unix timestamps in seconds are 10 digits for any date near today; the same instant in milliseconds is 13 digits. JavaScript's Date constructor expects milliseconds, while most Unix utilities and Python's time.time return seconds. The converter auto-detects which unit you pasted by digit count, but if you are writing code, divide or multiply by 1000 explicitly so the unit is unambiguous in the codebase.
Why is my timestamp showing a different time than I expect?+
Unix timestamps are timezone-agnostic — they count seconds since 1970-01-01 in UTC. When you convert a timestamp to a human-readable date, the displayed time depends on which timezone the converter renders it in. The tool shows both UTC and your local time so the offset is visible. If you need to display a timestamp in a fixed business timezone (say, US Eastern), pass the timezone explicitly in your code rather than relying on the user's locale.
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