Unix Timestamp Converter
Runs entirely in your browser — no data sent to any server
Example:
Enter a Unix timestamp to see the converted date and time.
Online Unix Timestamp Converter
Looking for an online Unix timestamp converter, epoch converter, or timestamp to date tool? Toolshelf turns Unix seconds or milliseconds into local time, UTC, and ISO 8601 — and converts a date/time back to Unix seconds and milliseconds — with no install, no signup, and no uploads. Choose the unit explicitly or use Auto-detect, then Copy the result you need.
Whether you are debugging API payloads, checking JWT exp claims with the JWT Decoder, or translating database epoch columns, this converter keeps the math precise and refuses values that JavaScript cannot represent accurately.
What you can do with this timestamp converter
- Convert Unix timestamps to local and UTC date/time instantly
- Choose seconds, milliseconds, or auto-detect the unit
- See clearly which unit auto-detect chose
- Convert a calendar date/time back to Unix seconds and milliseconds
- Copy individual fields or the full result set in one click
- Swap between Timestamp → Date and Date → Timestamp
- Strict validation for empty, invalid, decimal, and out-of-range values
- Private by design: conversion runs in your browser only
Unix timestamp vs epoch time vs ISO 8601
People search for Unix timestamp, epoch converter, and timestamp to date when they need the same outcome: map a machine-friendly number to a human-readable instant (or the reverse). A Unix timestamp counts seconds or milliseconds from the Unix epoch. ISO 8601 is a string form such as 2024-08-21T12:00:00.000Z.
This page is a private, browser-based epoch converter: paste a number or pick a date, confirm the unit, and copy local, UTC, ISO, seconds, and milliseconds without leaving your device.
Seconds or milliseconds?
Current-era Unix seconds are typically 10 digits (for example 1724241600). Milliseconds are typically 13 digits (for example 1724241600000). Mixing them up shifts the date by a factor of 1,000 — often into the wrong century. Use the Unit control, or Auto-detect, and read the detection label before you trust the result.
| Input | Unit | ISO 8601 (UTC) |
|---|---|---|
| 1724241600 | Seconds | 2024-08-21T12:00:00.000Z |
| 1724241600000 | Milliseconds | 2024-08-21T12:00:00.000Z |
| 0 | Seconds | 1970-01-01T00:00:00.000Z |
Why use an online epoch converter?
Hand-converting epoch values in a REPL is easy to get wrong when units differ. An online Unix timestamp converter reduces mistakes by showing local time, UTC, and ISO 8601 together, and by making the assumed unit explicit.
Toolshelf keeps the workflow simple: paste or pick a time, confirm seconds vs milliseconds, copy. There is no signup wall and no server-side processing of your values.
Common use cases
API and log debugging
Translate epoch values from JSON payloads, access logs, or database columns into readable local and UTC times.
JWT and token expiry
Check exp and iat claims without guessing whether the library stored seconds or milliseconds. For a full header and payload view, use the JWT Decoder.
Database timestamps
Confirm created_at / updated_at epoch values before writing migrations or fixing timezone bugs.
Cross-timezone collaboration
Share ISO 8601 and UTC alongside local time so teammates in other regions see the same instant.
QA and test fixtures
Generate exact Unix seconds or milliseconds for fixtures, seed data, and integration tests.
On-call incident review
Map alert timestamps to wall-clock times quickly while triage is still moving.
How to use the Unix timestamp converter
- 1Choose Timestamp → Date or Date → Timestamp.
- 2Enter a Unix timestamp and select Seconds, Milliseconds, or Auto-detect — or pick a local date and time.
- 3Review local, UTC, ISO 8601, and both Unix second and millisecond values.
- 4Click Copy or use per-field copy, Swap to reverse direction, or Clear to start over.
Privacy-first timestamp conversion
Some online converters send every value to a server. Toolshelf converts timestamps locally in the browser, which is better when you are inspecting production IDs, auth tokens, or internal event times. After the page loads, conversion does not require another network round-trip.
For details on cookies, logs, and advertising partners, read our Privacy Policy.
Tips for reliable timestamp handling
- Prefer storing UTC and convert to local time only for display.
- Document whether each API field is seconds or milliseconds.
- In JavaScript,
Date.now()andgetTime()return milliseconds — divide by 1,000 for Unix seconds. - When comparing schedule strings that include times, use Text Compare to spot edits quickly.
- For ISO date strings with offsets or date-only values, use the ISO 8601 Converter.
- For recurring jobs instead of one-off epochs, try the Cron Expression Generator.
Who this converter is for
- Backend and API developers decoding epoch fields
- SREs and on-call engineers reading alert and log timestamps
- QA engineers building time-based test fixtures
- Anyone who needs a private epoch ↔ date converter in the browser
Frequently asked questions
- What is a Unix timestamp?
- A Unix timestamp (also called epoch time) is the number of seconds — or sometimes milliseconds — that have elapsed since 00:00:00 UTC on 1 January 1970, not counting leap seconds. For example, 1724241600 is 2024-08-21T12:00:00.000Z.
- Do I need an account to use this Unix timestamp converter?
- No. Toolshelf Unix Timestamp Converter is available with no account, no usage limits, and no uploads required.
- Does my timestamp get uploaded to a server?
- No. Parsing and conversion run locally in your browser using JavaScript. Your values stay on your device.
- How does Auto-detect choose seconds vs milliseconds?
- If the absolute value is at least 1,000,000,000,000 (1e12), the tool treats the input as milliseconds; otherwise it treats it as seconds. The detected unit is shown under the Unit control so you can confirm or override it.
- Why does the tool reject decimal timestamps?
- Unix timestamps used in APIs and databases are whole numbers. Silently truncating a decimal would invent a different instant, so this converter asks you to enter a whole number of seconds or milliseconds instead.
- Are negative Unix timestamps supported?
- Yes. Negative values represent times before 1 January 1970 UTC, as long as they stay within the range JavaScript’s Date can represent.
- What happens with extremely large timestamps?
- Values outside JavaScript’s Date range (roughly ±100,000,000 days from the Unix epoch) are rejected with an error. The tool does not invent or clamp incorrect dates.
- What timezones does the converter use?
- Local date/time uses your browser timezone. UTC and ISO 8601 always refer to Coordinated Universal Time. When converting Date → Timestamp, the datetime picker uses local wall time.
- What is the difference between Unix seconds and milliseconds?
- Unix seconds count whole seconds since the epoch (about 10 digits today). Unix milliseconds multiply that by 1,000 (about 13 digits today). Many JavaScript APIs use milliseconds; many servers and databases use seconds.
- Does the Unix timestamp converter work on mobile?
- Yes. The layout stacks on small screens, unit controls remain tappable, and you can copy results without horizontal scrolling.
Ready to convert a Unix timestamp?
Scroll up to the converter, paste an epoch value or pick a date, and copy the result.
Back to converterExamples
Epoch to date
1735689600 is 2025-01-01 00:00:00 UTC when interpreted as seconds.
Use cases
- For Developers — Format JSON, test regex, decode JWTs, and work with timestamps.
- Everyday Tasks — Notes, passwords, QR codes, and quick file conversions.
What would you like to do next?
Continue working with the next step in this workflow. Recently used tools in this set are listed first.
- ISO 8601 Converter — Online ISO 8601 converter.
- Date Difference Calculator — Online date difference calculator.
- JWT Decoder & Inspector — Online JWT decoder and inspector.
- JSON Formatter & Minifier — JSON formatter online: beautify, minify, and validate JSON in your browser.
Related guides
Short articles that explain the problem this tool solves.
- What Is a Unix Timestamp? — A clear explanation of Unix epoch time, seconds vs milliseconds, and how to convert timestamps to local and UTC dates.
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