From API debugging to log analysis to JWT expiration — Unix timestamps are the universal language of time in software. Here's how they work, when to use each format, and how this tool handles every scenario.
Live Conversion
Output updates instantly as you type — bidirectional Unix ↔ date sync.
100% Client-Side
Nothing is uploaded. All conversions run in your browser sandbox.
14 Timezones
View the same moment in UTC, EST, JST, IST, and more with one click.
A Unix timestamp is an integer representing the number of seconds elapsed since the Unix Epoch — January 1, 1970 00:00:00 UTC. It is the most widely used time representation in computing because it is compact, sortable, timezone-neutral, and universally understood across languages and platforms.
Unlike human-readable dates, Unix timestamps have no ambiguity about format (MM/DD vs DD/MM), no daylight saving complications, and no timezone confusion. The integer 1704067200 means exactly the same moment everywhere in the world.
Key Reference Values
These landmark timestamps are useful for testing, validation, and understanding the range:
Unix timestamp reference
Epoch start → 0 (1970-01-01 00:00:00 UTC)
Y2K → 946684800 (2000-01-01 00:00:00 UTC)
Common test → 1704067200 (2024-01-01 00:00:00 UTC)
32-bit max → 2147483647 (2038-01-19 03:14:07 UTC)
Current (2025) → ~1740000000 (approx. Jun 2025)
Milliseconds → 13 digits (× 1000 from seconds)
Live Examples
Timestamp conversion examples — copy & try
Select any example below, copy the input, and paste it into the converter above to verify.
Input (Unix Timestamp)
1704067200
ISO 8601 Output
2024-01-01T00:00:00.000Z
💡 10-digit Unix timestamp in seconds. Paste into the converter above to see all formats instantly.
Seconds vs Milliseconds — Which Format Is It?
Misidentifying the format is the most common timestamp bug. Use digit count as your first check.
Format
Digits
Example
Used By
Seconds
10
1704067200
Linux, Python time.time(), PostgreSQL, JWT exp, most APIs
Python time.time_ns() / 1000, some logging systems
Nanoseconds
19
1704067200000000000
Go time.Now().UnixNano(), high-precision profiling
How to use this Timestamp Converter
1
Convert Tab
Enter a Unix timestamp or pick a date — both fields sync bidirectionally. Click 'Now' for the current time. Select a timezone to see local representations.
2
Diff Tab
Enter two timestamps A and B to calculate the exact difference in days, hours, minutes, and seconds. Swap button flips the inputs instantly.
3
Generate Tab
Use quick presets (yesterday, next week, etc.) or set a custom offset. Bulk generate up to 100 timestamps at a regular interval.
4
Range Builder
Set start and end timestamps to build a time range. Export as JSON, human-readable text, or get a cron expression suggestion.
Where Timestamps Are Used
API responses — created_at, updated_at, expires_at fields
Database columns — PostgreSQL, MySQL, MongoDB store Unix or ISO dates
Server logs — Nginx, Apache, and application logs use Unix time
JWT tokens — exp and iat claims are Unix timestamps in seconds
Cron jobs — schedule tasks using Unix-based intervals
File systems — creation and modification times as epoch values
Caching — TTL and expiration headers use timestamp arithmetic
Tool Features
Bidirectional Unix ↔ date conversion with live sync
Auto-detect seconds (10-digit) vs milliseconds (13-digit)
14 IANA timezones — UTC, EST, PST, JST, IST, and more
Dev format exports — MySQL, MongoDB, Python, JS, Swift
Timestamp diff calculator with human-readable breakdown
Quick presets and bulk timestamp generation
Range builder with JSON export and cron suggestions
100% browser-based — no data leaves your device
Code Examples
Converting Timestamps in Popular Languages
Copy these snippets for your project. Remember: most languages use seconds, but JavaScript uses milliseconds.
timestamp-conversionMulti-language
// JavaScript — uses milliseconds
const date = new Date(1704067200 * 1000);
date.toISOString(); // "2024-01-01T00:00:00.000Z"
Math.floor(Date.now() / 1000); // current Unix (seconds)
# Python
from datetime import datetime, timezone
datetime.fromtimestamp(1704067200, tz=timezone.utc)
# 2024-01-01 00:00:00+00:00
int(datetime.now(timezone.utc).timestamp()) # current Unix
// Go
time.Unix(1704067200, 0).UTC().Format(time.RFC3339)
// "2024-01-01T00:00:00Z"
# MySQL
SELECT FROM_UNIXTIME(1704067200);
# 2024-01-01 00:00:00
// Swift
Date(timeIntervalSince1970: 1704067200)
// 2024-01-01 00:00:00 +0000
The Year 2038 Problem
Systems using 32-bit signed integers to store Unix timestamps will overflow on January 19, 2038 at 03:14:07 UTC when the value exceeds 2,147,483,647. The counter wraps to a negative number, causing dates to jump back to December 13, 1901 — a problem analogous to Y2K.
Affected
32-bit embedded systems, legacy databases, old C/C++ applications using time_t on 32-bit platforms.
Safe
64-bit Linux, macOS, Windows, modern Node.js, Python 3, Go, and all major cloud databases.
Fix
Migrate to 64-bit time_t, use BIGINT columns in databases, and audit any code casting timestamps to int32.
💡 Use the Range Builder tab to calculate durations and verify your systems handle timestamps beyond 2038 correctly.
Understanding Timezones & Unix Time
Unix timestamps are always UTC — they represent an absolute point in time with no timezone offset. When you see a timestamp converted to "2024-06-15 14:30:00 EDT" vs "2024-06-15 18:30:00 UTC", both refer to the same moment; only the display format differs.