# Time Converter — Tips & Tricks

> Strategy and pitfalls for the Time Converter: seconds vs. milliseconds, the inverted POSIX signs of the Etc/GMT zones, and reading Timeago units right.

Source: https://www.jpkc.com/db/en/tools/time/tips/

Back to overview: [Time Converter](https://www.jpkc.com/db/en/tools/time/) · Open the live tool: [www.jpkc.com/tools/time/](https://www.jpkc.com/tools/time/)

The Time Converter is quick to operate — but time, time zones, and timestamps hide a few classic traps. This page collects what matters in practice. The technical groundwork is in the [manual](https://www.jpkc.com/db/en/tools/time/manual/).

## Seconds, not milliseconds

The most common pitfall: the Time Converter works with Unix timestamps in **seconds** (10 digits for current dates). Many systems — JavaScript first and foremost (`Date.now()`) — return **milliseconds** (13 digits), though. Enter a 13-digit millisecond number and you end up thousands of years in the future. Rule of thumb: if your value has 13 digits, **divide it by 1000** before entering it. A current seconds timestamp has 10 digits today.

## The Etc/GMT signs are the wrong way round

A genuine classic: the `Etc/GMT` zones follow the **POSIX convention** and therefore carry the **opposite sign** to the familiar UTC notation. Selecting `Etc/GMT+1` actually yields **UTC−1** (one hour *behind* Greenwich), and `Etc/GMT-5` yields **UTC+5**. So choosing "GMT+1" for Central Europe gives you exactly the opposite. Remember: with the `Etc/GMT` entries, mentally flip the sign — or just pick `CET` for Central Europe.

## The curated time-zone list knows no cities

The picker offers generic abbreviations (`CET`, `EET`, `PST8PDT` …) and `Etc/GMT` offsets — **no** IANA city zones like `Europe/Berlin` or `America/New_York`. Some of the generic abbreviations (e.g. `CET`, `EST5EDT`, `PST8PDT`) account for daylight saving, whereas the plain `Etc/GMT` offsets **don't** — they're fixed shifts with no DST switch. If you care about a specific city's DST-accurate local time, check the result deliberately and pick an abbreviation with the right DST behavior.

## Timeago: each line is a total

Read the `Timeago` output correctly: the lines `Years`, `Months`, `Day`, `Hours`, `Minutes`, `Seconds` are **not** a decomposition of a single gap, but **each the full distance in that one unit**. "Months: 14" and "Day: 425" describe the same period, measured once in months and once in days. If you want the *decomposed* form "X years, Y months, Z days", use the **precise breakdown** on the last line.

## Time zone and language apply to all tabs

**Language Format** and **Timezone** sit in the card footer and act **on Current, Convert, and Timeago at once**. So set them before converting. Note: the language changes only the *formatting*, not the instant; the time zone changes only the *display*, not the underlying Unix timestamp (which is why line 1 stays the same across all time zones).

## Pause the live clock to copy

In the **Current** tab the clock ticks on every second — awkward when you want to select a value calmly. Click **Start/Stop Timer** to freeze the display, copy the value (or use the clipboard button), then start it again. The output field is also editable, in case you want to adjust a value before copying.

## Server time as an independent reference

If you doubt your local machine clock, grab the server clock's timestamp with **Get Server Time** in the Convert tab. That way you spot a mis-set local clock before it feeds you wrong conversions. For your own scripts the two endpoints `/tools/time/time/` (seconds) and `/tools/time/mtime/` (microtime) are available directly as plain text.

## Combine with other JPKCom tools

- **[Cron generator](https://www.jpkc.com/db/en/tools/cron/)** — when you don't just want to convert a single moment but formulate a *recurring* schedule; convert the next run back into a readable date here.
- **[UUID generator](https://www.jpkc.com/db/en/tools/uuid/)** — time-based UUIDs (v1, v7) carry a timestamp inside them; use the Time Converter to place it.
- **[Hash generator](https://www.jpkc.com/db/en/tools/hash/)** — for time-stamped records whose integrity you want to secure with a checksum.

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The full function reference is in the [manual](https://www.jpkc.com/db/en/tools/time/manual/), concrete walkthroughs in the [examples](https://www.jpkc.com/db/en/tools/time/examples/). You can try everything in the [tool](https://www.jpkc.com/tools/time/).