How to convert Unix timestamp to date?

Paste the timestamp (e.g. 1704067200 for seconds or 1704067200000 for milliseconds), choose Seconds/Milliseconds/Auto and click Convert to Date. The tool does new Date(timestamp*1000) or new Date(timestamp) and shows GMT, local, ISO 8601 and relative time such as 2 years ago.

How to convert date to Unix timestamp?

Pick a date and time via the datetime picker or type an ISO string like 2024-01-01T00:00:00Z and click Convert to Timestamp. The tool does Date.parse or new Date(value).getTime() divided by 1000 for seconds or raw milliseconds, handling local timezone correctly.

How to get current timestamp?

The live Current Timestamp card updates every second showing both seconds and milliseconds, plus ISO and human date. Click Copy to copy sec or ms instantly, or click Use in Converter to prefill the converters.

Timestamp Converter - Convert Unix Timestamp Online Free

🟢 Current Timestamp — Live

Unix Seconds (10 digits)

—

seconds since 1970-01-01 00:00:00 UTC

Unix Milliseconds (13 digits)

—

Date.now() • JavaScript

ISO 8601 (UTC)

—

Local Time

—

UTC String

—

● updating every second Auto-updates every 1000ms • pause to freeze for debugging • times are generated with Date.now()

📥 Input Timestamp → Date

Unix Timestamp (seconds or milliseconds)

Auto: < 1e12 → seconds ×1000, ≥ 1e12 → milliseconds • Supports negative (before 1970) & decimals

Human Date — Local—

Human Date — UTC (GMT)—

ISO 8601—

UTC ISO—

Relative Time—

Seconds / Milliseconds—

📅 Input Date → Timestamp

Date & Time (local) Uses your browser timezone (—) • step 1s

Or paste ISO / UTC string Supports ISO 8601, RFC 2822, and Date.parse formats

Unix Seconds—

Unix Milliseconds—

ISO 8601 (local → UTC)—

UTC String—

Relative—

Seconds ×1000 = Milliseconds • Auto-detect handles both

What is Unix Timestamp? Epoch Time, POSIX Time & Unix Time Explained

A Unix timestamp — also called epoch time, POSIX time, Unix time or simply timestamp — is the number of seconds (and in JavaScript, milliseconds) that have elapsed since 00:00:00 UTC on Thursday, 1 January 1970, known as the Unix epoch. It does not count leap seconds. Every second increments the integer by one: 0 is 1970-01-01 00:00:00 UTC, 86400 is 1970-01-02 (one day later), 1704067200 is 2024-01-01 00:00:00 UTC, and 2147483647 is the famous 2038-01-19 03:14:07 UTC when signed 32-bit timestamps overflow. Our timestamp converter at html-compiler.com/timestamp-converter/ converts in both directions: convert Unix timestamp to date (seconds or milliseconds → human-readable GMT, local, ISO 8601 and relative time like “2 hours ago”) and convert date to Unix timestamp (human date → seconds and milliseconds) with a live current timestamp clock that ticks every second.

Why two units? Traditional Unix, PHP, Python time.time(), Ruby and JWT iat/exp use seconds (10 digits) — e.g. 1725427200. JavaScript Date.now(), Java System.currentTimeMillis(), and many REST APIs use milliseconds (13 digits) — e.g. 1725427200000. Multiply seconds by 1000 to get milliseconds; divide milliseconds by 1000 to get seconds. The converter’s Auto-detect mode does this automatically: numbers with absolute value < 1e12 are treated as seconds and internally computed as new Date(ts * 1000), while ≥ 1e12 are treated as milliseconds via new Date(ts). You can also force Seconds or Milliseconds from the dropdown. Negative timestamps are also supported — they represent dates before 1970, e.g. -86400 is 1969-12-31 00:00:00 UTC — useful for historical data.

Timestamp	Unit	Human Date (UTC)	Example Context / API
`0`	seconds	1970-01-01 00:00:00 UTC	Epoch origin
`1704067200`	seconds	2024-01-01 00:00:00 UTC	PHP `time()`, Python `int(time.time())`, JWT
`1704067200000`	milliseconds	2024-01-01 00:00:00 UTC	JS `Date.now()`, `new Date().getTime()`
`2147483647`	seconds	2038-01-19 03:14:07 UTC	32-bit signed max — Y2038 problem
`-2208988800`	seconds	1900-01-01 00:00:00 UTC	Historical dates (negative)
`253402300799`	seconds	9999-12-31 23:59:59 UTC	Far future limit for `Date`

Under the hood we use only native browser APIs: Date.now() for live, new Date(value) for parsing, date.getTime() and Math.floor(date.getTime()/1000) for conversion, date.toISOString() for ISO 8601, date.toUTCString() for GMT and date.toLocaleString() for local time. No server, no library, no rounding surprise — the same code you would write in Node or in a browser console, now wrapped in a light card UI inspired by htmlbeautifier.org/css.

Why Convert Timestamps? Benefits for Developers, APIs & Debugging

Raw timestamps are compact, timezone-free and perfect for storage and sorting — but they are unreadable to humans. Converting unlocks everyday workflows where a number must become a calendar date or vice versa.

Benefit	How Timestamp Converter Helps	Who Benefits Most
🐛 Debug APIs & Logs	Turn `exp: 1725427200` or database `created_at: 1704067200000` into “Sep 4, 2024 00:00 UTC — 2 years ago” instantly	Backend devs, QA, SRE reading JSON/logs
🔐 JWT & Session Expiry	Decode `iat`, `exp`, `nbf` claims to check if token is expired or not yet valid	Auth engineers, frontend calling OAuth
🗄️ Database Migration	Convert legacy integer epoch columns to `DATETIME` or ISO for Postgres/MySQL, and back	DBAs, data engineers
📊 Analytics & CSV	Turn `event_time: 1719849600` in CSV/JSON to human date for Excel/Sheets charts	Analysts, marketers
⚙️ Cron & Scheduling	Pick “2025-12-31 23:59” → get `1767225540` to set cron, TTL or cache expiry correctly	DevOps, SRE
🌐 Timezone Correctness	See both UTC and local side-by-side to avoid off-by-hours bugs from forgetting `Z`	Full-stack devs shipping global apps
🧪 Test Data	Generate edge timestamps (leap day, Y2038, negative) to test validation	QA, students

Conversely, date to timestamp is needed whenever you must produce an epoch value: setting expiresAt = Math.floor(Date.now()/1000) + 3600 for a one-hour cookie, seeding a database, or calling an API that expects ?since=1725427200. Doing this by mental math is error-prone — off by 1000× if you mix seconds and milliseconds. Our tool handles that, shows both units, and highlights relative time (“in 3 days” vs “2 years ago”) so you get immediate context.

Features of html-compiler.com Timestamp Converter (Free, Fast, Private)

Inspired by htmlbeautifier.org/css’s clean light-card design but rebuilt for time conversion, this timestamp converter packs everything into three cards with no backend:

Live Current Timestamp (tick every 1000ms): Top card shows Unix seconds (floor of Date.now()/1000) and Unix milliseconds (Date.now()) updating live via setInterval(1000), plus ISO 8601, local and UTC strings. Pause to freeze for copy, then Copy Seconds or Copy Milliseconds via navigator.clipboard.writeText. One click “Use in Converter” prefills the timestamp input — ideal when you need “now” as a baseline.
Timestamp → Date with Auto Seconds/Milliseconds: Paste any integer or float like 1725427200, 1725427200.123, 1725427200000 or -86400. Choose Auto-detect (default), Seconds or Milliseconds. Click Convert: we run new Date(ts * 1000) for seconds or new Date(ts) for milliseconds, then display Local (toLocaleString), UTC (toUTCString), ISO (toISOString), UTC ISO, Relative and both units together. Handles decimals and invalid input with a red “Invalid timestamp” message instead of Invalid Date crash.
Date → Timestamp (picker + ISO text): Two inputs in one card: a native input type="datetime-local" (step 1 second, local timezone) and a free-form text field for ISO/RFC strings like 2024-01-01T00:00:00Z, 2024-01-01 00:00:00 UTC or Jan 1, 2024 12:00 PM. Click Convert to Timestamp: we do new Date(value) or Date.parse(text) and output Unix seconds (Math.floor(date.getTime()/1000)) and milliseconds (date.getTime()), plus ISO, UTC and relative. Timezone name is shown via Intl.DateTimeFormat().resolvedOptions().timeZone.
Human Date + ISO 8601 + Relative Time: Every conversion shows three forms developers actually use: human-readable (e.g. Wednesday, September 4, 2024 2:30:00 PM GMT+05:30), machine-friendly ISO (2024-09-04T09:00:00.000Z) and contextual relative (“in 2 hours”, “3 days ago”, “just now”). Relative is computed from Date.now() difference with thresholds for seconds, minutes, hours, days, months and years.
One-Click Copy & Cross-Use: Each output has Copy buttons (Clipboard API with execCommand fallback). “Use timestamp in Timestamp → Date” and “Use date in Date → Timestamp” buttons copy the result into the opposite converter for round-trip testing without retyping.
Light Cards, Monospace Values, Orange Actions: 1000px centered wrap, rounded cards, monospace ui-monospace values, orange primary buttons (#f97316) and dark secondary (#0f172a) matching the htmlbeautifier family — comfortable for long numbers and 24-hour strings.
100% Client-Side & Lightweight: No server, no cookies, no signup. Under 15KB local JS, zero dependency besides native Date. Works offline after first load, even on low-end devices and 3G labs.

How to Use Timestamp Converter — Step-by-Step Guide

Method 1: Convert Unix Timestamp to Date (Fastest)

Copy a timestamp from an API response, database row, JWT payload or log — e.g. 1725427200 (seconds) or 1725427200000 (milliseconds). Paste it into 📥 Input Timestamp, leave Auto-detect (or force Seconds/Milliseconds if you know the source), then click 🔄 Convert to Date (or press Ctrl+Enter). The card below shows Human Date — Local (your timezone), Human Date — UTC (GMT), ISO 8601 (2024-09-04T00:00:00.000Z), UTC ISO, Relative and the dual Seconds / Milliseconds pair. Example: 1704067200 → Monday, January 1, 2024 12:00:00 AM GMT+00:00 • 2024-01-01T00:00:00.000Z • ~2 years ago.

Method 2: Convert Date to Unix Timestamp

Pick a date and time via the 📅 Date & Time (local) picker — it opens the browser’s native calendar with second precision — or paste an ISO string like 2025-12-31T23:59:59Z or 2024-09-04 09:00 UTC into the text field. Click ↩ Convert to Timestamp. Output shows Unix seconds (10-digit, e.g. 1735689599) and milliseconds (13-digit, e.g. 1735689599000) plus ISO, UTC and relative. The timezone badge confirms which zone was used (e.g. Asia/Kolkata or America/New_York), so you can spot off-by-hours mistakes before you ship. Use 🕒 Now to prefill the current moment.

Method 3: Use Live Current Timestamp

Need “now” for a quick test? Watch the 🟢 Current Timestamp — Live card at the top — it ticks every second. Click 📋 Copy Seconds or 📋 Copy Milliseconds to copy instantly for curl, Postman or code, or click ↘ Use in Converter to drop the current seconds into the timestamp input and auto-convert. Hit ⏸ Pause to freeze the clock when you need a stable value to screenshot or share, then ▶ Resume to continue.

After conversion: Use 📋 Copy on ISO or timestamp values, or the cross-use buttons to round-trip: convert a date to timestamp, then feed that timestamp back into the other direction to verify you get the original date. Pro tip: Ctrl+Enter converts timestamp → date and Ctrl+Shift+D converts date → timestamp without touching mouse.

Unix Timestamp Seconds vs Milliseconds vs ISO — Comparison

Format	Example	Length / Range	How to Create (JS)	When to Use
Seconds (Unix)	`1725427200`	10 digits • fits 32-bit until 2038	`Math.floor(Date.now()/1000)` or `Math.floor(date.getTime()/1000)`	PHP, Python, Go, JWT `exp`, Unix, Postgres epoch
Milliseconds (JS)	`1725427200000`	13 digits • native JS	`Date.now()` or `date.getTime()`	JavaScript, Java, REST APIs, MongoDB, Firebase
ISO 8601	`2024-09-04T00:00:00.000Z`	Human + machine, ends with `Z` for UTC	`new Date(ts*1000).toISOString()`	APIs, JSON, logs, storage — unambiguous
UTC String	`Wed, 04 Sep 2024 00:00:00 GMT`	RFC 7231 / email style	`date.toUTCString()`	HTTP headers, email Date, debugging
Local String	`9/4/2024, 5:30:00 AM IST`	Depends on browser locale/timezone	`date.toLocaleString()`	UI display for end users

Before vs After Example — Timestamp Converter in Action

Before (Input)	After Convert to Date	After Convert Back to Timestamp
1704067200 (sec)	Mon Jan 01 2024 00:00:00 GMT+0000 `2024-01-01T00:00:00.000Z` ~2 years ago	1704067200 sec 1704067200000 ms
1725427200000 (ms)	Wed Sep 04 2024 00:00:00 GMT+0000 `2024-09-04T00:00:00.000Z`	1725427200 sec
2024-09-04T00:00:00Z (ISO)	— input is date —	1725404800 sec 1725404800000 ms

// Timestamp (seconds) → Date
const ts = 1704067200; // seconds
const d  = new Date(ts * 1000);
console.log(d.toISOString()); // 2024-01-01T00:00:00.000Z
console.log(d.toUTCString()); // Mon, 01 Jan 2024 00:00:00 GMT
console.log(d.toLocaleString()); // 1/1/2024, 12:00:00 AM (local)

// Date → Timestamp (seconds & milliseconds)
const date = new Date('2024-01-01T00:00:00Z');
const sec = Math.floor(date.getTime() / 1000); // 1704067200
const ms  = date.getTime();                    // 1704067200000

// Current timestamp live
const nowSec = Math.floor(Date.now() / 1000);
const nowMs  = Date.now();

Pro Tips, Timezones & Browser Compatibility

Expert Tips to Avoid Timestamp Bugs

Never mix sec and ms: Passing milliseconds to an API expecting seconds makes the date 1000× in the future (year 54770). If the output looks year 1970 or 57000+, you used the wrong unit — switch the dropdown or rely on Auto-detect. Our output shows both so you can compare.
Always be explicit with Z: 2024-01-01T00:00:00 (no Z) is parsed as local time, while 2024-01-01T00:00:00Z is UTC. A missing Z can shift by your timezone offset (e.g. +05:30). For APIs, always send toISOString() which ends with Z.
Relative time sanity check: “in 5 hours” vs “5 hours ago” tells you immediately if you set expiry in the past. Use it to validate cron and JWT exp before deploying.
Handle leap seconds and DST: Unix time ignores leap seconds, so 23:59:60 UTC never appears as a timestamp. Daylight saving shifts affect toLocaleString but not the underlying UTC seconds — store UTC, display local.
32-bit overflow (Y2038): If you must store in signed 32-bit, max is 2147483647 (2038-01-19). For new systems store 64-bit or ISO strings. JS Date safely handles up to ±8,640,000,000,000,000 ms (~275k years).
Validate before converting: We check isFinite(ts) and !isNaN(Date.parse(...)). Empty or text like abc shows a red “Invalid timestamp — enter a number like 1704067200” instead of blank.
Sync your clock: The live clock uses the device clock. If it is off by minutes, timestamps you generate will be off too — enable NTP/auto time in OS settings for accuracy.

Supported Standards

POSIX / Unix epoch (seconds since 1970-01-01T00:00:00Z), JavaScript Date milliseconds since epoch, ISO 8601 (YYYY-MM-DDTHH:mm:ss.sssZ), RFC 2822 / UTC string (toUTCString), and Intl.DateTimeFormat for local timezone. Uses only Date.now, new Date, getTime, toISOString, toUTCString, toLocaleString, Date.parse — compatible with every evergreen browser.

Browser compatibility: Chrome 90+, Firefox 90+, Safari 14+, Edge 90+ — uses only Clipboard API and native Date. Live ticker uses setInterval(1000) and pauses on document.hidden to save battery.

Target Keywords & Search Intent Map (SEO Authority)

We built this page to rank for the full cluster around timestamp converter — covering every tool + informational intent naturally, mirroring htmlbeautifier.org’s successful light-card structure:

Primary Keyword	Monthly Volume*	Intent	How We Cover It
timestamp converter	12,100	Tool	Title, H1, hero, live + dual converters, URL /timestamp-converter/
unix timestamp converter	8,100	Tool	H1, TSP card, seconds/ms handling, FAQ
convert unix timestamp	4,400	Tool	Timestamp → Date card, examples, code snippet
unix time converter	3,600	Tool	Comparison table, what-is section
epoch converter / epoch time	5,400	Tool	SEO synonyms in H2, tables
convert date to timestamp	2,900	Tool	Date → Timestamp card, picker + ISO
current timestamp / timestamp now	2,400	Tool	Live clock card, Now buttons
unix timestamp to date	1,900	Learn + Tool	Before/after table, Pro tips

*Estimated volumes for illustration — we target all variants naturally through H2s, tables, and FAQPage schema for featured snippets.

Whether you searched timestamp converter, unix timestamp converter, epoch converter, convert timestamp to date, date to timestamp, current timestamp — this page converts both ways with ISO, UTC, local and relative time in one lightweight view. Bookmark html-compiler.com/timestamp-converter/ alongside JSON Beautifier • URL Encoder • Base64 Encoder • HTML Beautifier.

Frequently Asked Questions (FAQ)

What is Unix timestamp and what is epoch time?

Unix timestamp (epoch time, POSIX time) is the count of seconds since 1970-01-01 00:00:00 UTC, the Unix epoch. 0 is the epoch itself, 1704067200 is 2024-01-01 00:00:00 UTC. It is timezone-independent — the same number means the same instant worldwide. Milliseconds is the same count ×1000, as used by JavaScript Date.now().

How do I convert Unix timestamp to date online?

Paste the number into 📥 Input Timestamp (e.g. 1725427200 for seconds or 1725427200000 for ms), keep Auto-detect or choose Seconds/Milliseconds, then click 🔄 Convert to Date. You get Human Date (local + GMT), 2024-09-04T00:00:00.000Z ISO, UTC string and relative time like “2 days ago”. Handles negative and decimal timestamps too.

How do I convert date to Unix timestamp?

Use the 📅 Input Date picker to choose a local date/time, or paste an ISO string like 2024-01-01T00:00:00Z into the text field, then click ↩ Convert to Timestamp. We show both Unix seconds (Math.floor(date.getTime()/1000)) and milliseconds (date.getTime()) plus ISO and relative. The displayed timezone (e.g. Asia/Kolkata) confirms which zone was applied.

What is difference between seconds and milliseconds timestamp — which should I use?

Seconds (10 digits, e.g. 1725427200) is classic Unix — used by PHP, Python, JWT and Postgres. Milliseconds (13 digits, e.g. 1725427200000) is native JavaScript/Java — used by Date.now(), MongoDB and many REST APIs. Rule: if you divide by 1000 and get a year near 2024-2026, it was milliseconds. Our converter shows both, so you can pick the one your API expects. Multiply/divide by 1000 to convert.

How do I get current timestamp?

Look at the 🟢 Current Timestamp — Live card at the top — it updates every second. Click 📋 Copy Seconds for Math.floor(Date.now()/1000) or 📋 Copy Milliseconds for Date.now(), or ↘ Use in Converter to prefill the input. You can also click 🕒 Now inside either converter card.

Does this handle timezones correctly?

Yes. Timestamp itself is UTC-based. We show both Local (toLocaleString with your OS timezone, shown as badge e.g. America/New_York) and UTC/GMT (toUTCString and toISOString ending with Z). For Date → Timestamp, the datetime-local picker is interpreted as local time, while an ISO string ending with Z is interpreted as UTC — matching browser Date.parse spec, so no surprise shifts.

Is this timestamp converter free and private?

Yes — 100% free, client-side, no signup, no server upload. All math is native Date in your browser tab, so timestamps and dates never leave your device. Works offline after first load. Bookmark html-compiler.com/timestamp-converter/ for instant access.

Best Timestamp Converter Online Free in 2026 — Start Converting Now

Whether you are a student learning what epoch time means, a developer decoding a JWT exp before it expires, or an SRE turning a log’s 1725427200 into a readable date, a reliable timestamp converter saves minutes on every debug. Stop multiplying by 1000 in your head or opening a console — paste the Unix timestamp above and hit 🔄 Convert to Date to see human date, ISO 8601, UTC and “3 hours ago” instantly, or pick a date and hit ↩ Convert to Timestamp to get seconds and milliseconds ready for your API. And when you just need “now”, the live current timestamp ticks at the top — copy seconds or milliseconds in one click. Bookmark html-compiler.com/timestamp-converter/ — the lightweight, private, evergreen timestamp converter, Unix timestamp converter and epoch converter for 2026 and beyond. Explore our other free tools: HTML Compiler • HTML Beautifier • CSS Beautifier • JS Beautifier • JSON Beautifier • URL Encoder • Base64 Encoder — all client-side, all free forever.

Timestamp Converter — Unix Time to Date & Back