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Timestamp Converter | Convert Unix Epoch to Readable Dates

Convert Unix timestamps to human-readable dates and back, in seconds or milliseconds, with UTC and your local time shown. The developer's essential tool for debugging APIs, logs and databases.

Last updated: June 2026 · Free · No sign-up required

Timestamp → Date

Date → Timestamp

Quick reference

TimestampUTC date
01 Jan 1970 00:00:00
10000000009 Sep 2001 01:46:40
175000000015 Jun 2025 15:06:40
200000000018 May 2033 03:33:20

info Unix Timestamp Converter

Free developer tools calculator — enter your numbers and get an instant, accurate result.

info Private by design

Everything runs locally in your browser. No uploads, no accounts, no tracking.

info Works everywhere

Fully responsive and mobile-friendly — calculate on any device, any time.

info Educational

Includes the formula and step-by-step explanation so you understand the math, not just the answer.

Interpretation guide

Digit countUnit
10 digitsSeconds (standard Unix)
13 digitsMilliseconds (JavaScript)
16 digitsMicroseconds
19 digitsNanoseconds (Go, some DBs)

lightbulb Worked example

Let's say you are using the Unix Timestamp Converter. A free tool to convert Unix epoch timestamps to human-readable dates and vice versa. Essential for developers working with APIs, databases, and log files. Enter the values that match your situation into the input fields and press calculate — using realistic numbers makes the result directly useful for you.

Result: The calculator instantly applies the formula Date = epoch + N seconds since 1970-01-01T00:00:00Z; ms timestamps ÷ 1000 and returns the result with appropriate precision.

What this means: Read the result in the context of what you are measuring. The step-by-step breakdown lets you confirm the math and understand which input most affects the outcome.

Formula & methodology

Formula: Date = epoch + N seconds since 1970-01-01T00:00:00Z; ms timestamps ÷ 1000

The Unix Timestamp Converter is built on a well-established calculation method. It uses the formula Date = epoch + N seconds since 1970-01-01T00:00:00Z; ms timestamps ÷ 1000 to turn your inputs into a reliable result. A free tool to convert Unix epoch timestamps to human-readable dates and vice versa. Essential for developers working with APIs, databases, and log files. The steps are shown on the page so you can follow the reasoning from input to output.

  1. Paste a timestamp — the tool auto-detects seconds vs milliseconds by digit count — or pick a date to convert the other way.
  2. Conversion uses the Unix epoch (1 Jan 1970 UTC) with your local zone displayed alongside UTC.
  3. A live "current epoch" ticker is included for quick reference.

Worked example: 1750000000 → Sunday, 15 June 2025 15:06:40 UTC; the same moment in JavaScript milliseconds is 1750000000000.

Authoritative source: MDN Web Docs

Frequently asked questions

What is a Unix timestamp?
The Unix Timestamp Converter is free, private, and accurate: it runs entirely in your browser (no uploads, no accounts), applies the standard calculation, and explains each step so you can verify the result. A free tool to convert Unix epoch timestamps to human-readable dates and vice versa. Essential for developers working with APIs, databases, and log files. There is no limit on usage, and it works on any device.
Why is my timestamp 13 digits?
A 13-digit timestamp is in MILLISECONDS — the value in seconds multiplied by 1,000 — which JavaScript's Date.now() and most modern APIs produce. The converter detects the digit count and divides by 1,000 before converting, so 13-digit timestamps (like 1787xxx0000000) are handled automatically alongside 10-digit seconds values.
How do I get the current epoch time?
Enter the required values into the input fields and press the calculate button. The tool applies the formula Date = epoch + N seconds since 1970-01-01T00:00:00Z; ms timestamps ÷ 1000 and returns the result with a short explanation of each step, so you can check the working yourself.
What is the year-2038 problem?
On 32-bit systems, Unix time is stored as a signed 32-bit integer, which overflows on January 19, 2038 — the clock wraps to 1901, breaking timestamps and any software that depends on them. 64-bit systems store time as a 64-bit integer and are safe for billions of years. The converter handles the full 64-bit range, so it is unaffected either way.
Do Unix timestamps have time zones?
No — a Unix timestamp is the number of seconds since 1970-01-01T00:00:00Z, an instant in time that is identical worldwide. The time zone only affects how that instant is DISPLAYED as a local date and time. The converter shows your local time and UTC for the same timestamp, so you can see that the underlying instant never changes.
How do I tell seconds apart from milliseconds?
Count the digits — 10 digits means seconds (1,700,000,000 ≈ late 2023), 13 means milliseconds. JavaScript's Date.now() returns milliseconds while most APIs and Unix systems use seconds. The scale is detected automatically and both are shown.
Why does one timestamp show different times in different places?
The timestamp itself is always UTC — seconds since 1970-01-01T00:00:00Z. Only the display timezone differs: both UTC and local time are shown. A timestamp is a single instant; the clock reading depends on where you stand.
What is the Year 2038 problem?
32-bit signed integers max out at 2,147,483,647 seconds — 03:14:07 UTC on 19 January 2038 — then overflow to negative. Modern 64-bit systems are unaffected, but old embedded systems and file formats still store 32-bit times. Timestamp work touching legacy systems needs to account for it.
Can timestamps represent dates before 1970?
Yes — negative values count backward from the epoch, so −86400 is 1969-12-31, and negatives are handled fine. Just remember that some databases and languages with unsigned time types cannot represent them.

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