How are milliseconds, microseconds, and nanoseconds derived?

Browsers expose time at millisecond precision. Seconds are the millisecond value divided by 1000 and floored, while microseconds and nanoseconds are the millisecond value scaled up by 1,000 and 1,000,000.

Are the microsecond and nanosecond digits real precision?

No. Because the browser clock only resolves to milliseconds, the extra digits are zero-filled. They are convenient when a system expects those units but should not be read as sub-millisecond accuracy.

Is the timestamp in my local timezone?

No. Unix time is always counted from the UTC epoch, so it is the same instant everywhere. The ISO line at the bottom shows that instant formatted in UTC for reference.

How often does it update?

The display refreshes roughly twenty times a second, so the milliseconds and finer values tick visibly while the page is open.

What is the Current Unix Timestamp?

See the current Unix timestamp live in seconds, milliseconds, microseconds, and nanoseconds, with the matching UTC ISO time. Each value updates many times per second and is one click to copy. It runs free in your browser on Gera Tools, with nothing uploaded.

Current Unix Timestamp

Name: Current Unix Timestamp
Creator: Gera Tools
License: https://creativecommons.org/licenses/by/4.0/

The live current Unix timestamp, in four units

This tool shows the current Unix timestamp right now and keeps it ticking — refreshing roughly twenty times per second — presenting the same instant in seconds, milliseconds, microseconds, and nanoseconds alongside the matching UTC ISO date-time. It is built for developers who need a quick epoch value to paste into an API call, a database record, a test fixture, a log query, or a JWT expiry field.

What is a Unix timestamp?

Unix time counts the number of seconds elapsed since the Unix epoch: 00:00:00 UTC on 1 January 1970. It is timezone-free — the same number everywhere on Earth at the same instant — and it is the most widely used way software represents a point in time as a single integer.

Present-day values look roughly like this:

In seconds (10 digits): for example 1,700,000,000 range
In milliseconds (13 digits): 1,700,000,000,000 range
In microseconds (16 digits): 1,700,000,000,000,000 range
In nanoseconds (19 digits): 1,700,000,000,000,000,000 range

If you see a 13-digit number, it is almost certainly milliseconds. A 10-digit number is seconds.

How the values are derived

JavaScript’s Date.now() returns milliseconds since the epoch. The tool reads that value and derives the other units:

const ms  = Date.now();
const sec = Math.floor(ms / 1000);
const µs  = ms * 1000;      // scale up
const ns  = ms * 1000000;   // scale up

Because the browser clock only resolves to the millisecond, the microsecond and nanosecond values are the millisecond value scaled up — the last three (µs) or six (ns) digits are always zeros. They give you the correct order of magnitude for a system that expects those units without carrying genuine sub-millisecond precision.

Which precision to use and where

Unit	Digit count (today)	Typical use
Seconds	10	Unix APIs, cron, JWT `exp`/`iat`, POSIX `time_t`
Milliseconds	13	JavaScript `Date`, JSON payloads, many logging systems, Kafka offsets
Microseconds	16	PostgreSQL `TIMESTAMPTZ`, some distributed tracing systems
Nanoseconds	19	Go `time.UnixNano()`, InfluxDB, high-frequency trading timestamps

The Year 2038 problem — and why it no longer matters for most code

Systems that store Unix time in a signed 32-bit integer overflow on 19 January 2038 at 03:14:07 UTC, when the value exceeds 2,147,483,647 seconds. If you are working with legacy embedded systems, databases with INT timestamp columns, or 32-bit C code, be aware of this. Modern languages and 64-bit databases store timestamps as 64-bit integers, pushing the overflow billions of years into the future.

Tips for common tasks

Checking if a token has expired: compare the current seconds timestamp to the JWT exp field. If now > exp, the token is expired.
Log correlation: include the milliseconds timestamp in every log line so you can sort logs from multiple services chronologically even when they span different machines and timezones.
Test fixtures: generate timestamps at a known past moment by converting a date with the Unix Timestamp Converter; paste the result directly into your test data.
Relative time in code: const fiveMinutesFromNow = Date.now() + 5 * 60 * 1000; — working in milliseconds lets you use simple arithmetic without converting back and forth.