Timestamp Converter

Timestamp Converter Tool Guide

What you will get (overview)

• Seconds vs milliseconds: 10-digit vs 13-digit timestamps to avoid “wildly wrong years”.
• Local vs UTC: a timestamp is absolute; formatting is timezone-dependent.
• Engineering troubleshooting: validate timestamp fields in APIs, logs, alerts, and expiration logic.
• Privacy boundary: OnesAPK converts locally (Client-side) with no server upload.

Typical use cases (engineering-oriented)

• API debugging: verify request/response timestamps against expected windows.
• Log analysis: turn Unix times into readable datetimes quickly.
• Cross-timezone collaboration: avoid confusion between local time, UTC, and DST.

Quick glossary

• [Unix timestamp] Seconds/milliseconds since 1970-01-01 00:00:00 UTC.
• [UTC] Coordinated Universal Time, commonly used as a protocol/backend baseline.
• [Timezone] A region’s offset/rules used when formatting timestamps.
• [DST] Daylight Saving Time, which can shift local clocks seasonally.

Best practices

• Identify units first: 10 digits is usually seconds; 13 digits is usually milliseconds.
• Standardize in your system: prefer UTC or explicitly include timezone offsets in strings.
• Use ISO-8601 with offset: e.g., 2024-01-01T12:00:00+08:00 or ...Z.
• Boundary note: this tool does not provide legal/compliance advice; follow your organization’s policies when handling production logs or user data.

Related tools

• OnesAPK Toolbox (Home) Explore more privacy-friendly, client-side tools
• OnesAPK URL Parser Inspect URLs containing timestamp query parameters

1. What this timestamp tool can do

• Convert Unix timestamps to human‑readable date/time
  Supports both second‑based and millisecond‑based Unix timestamps and converts them into readable local time or UTC.

• Convert date/time strings to Unix timestamps
  Paste a common date/time string (including ISO strings with timezone) to get the corresponding Unix timestamp in seconds and milliseconds.

• Switch between local time and UTC
  Use the display mode toggle at the top to see results either in your local timezone or in UTC.

• View world time for multiple cities
  Quickly compare the same moment in different cities (such as Beijing, New York, London, Tokyo, Sydney, etc.).

• Fill in the current time with one click
  Use the “Use current time” button to instantly populate both the timestamp and date/time inputs with the current moment.

2. Basic usage

2.1 Unix timestamp → date/time

1. In the “Unix timestamp to date/time” section on the left:

   • Enter a Unix timestamp into the input field;
   • Choose seconds or milliseconds using the radio buttons above.

2. Click “Convert to date/time”:

   • The result card below will show:
     • The formatted date/time;
     • The Unix timestamp in seconds;
     • The Unix timestamp in milliseconds.
   • If you are in UTC mode, the formatted result is shown in UTC; otherwise it uses your local timezone.

3. To reset the input:

   • Click “Clear” to empty the field and clear the result.

2.2 Date/time → Unix timestamp

1. In the “Date/time to Unix” section on the right:

   • Enter a date/time string, such as:
     • 2024-01-01 12:00:00
     • 2024-01-01T12:00:00+08:00
     • 2024/01/01 12:00:00, etc.

2. Click “Convert to timestamp”:

   • The result card will show the formatted date/time and the corresponding Unix timestamp in seconds and milliseconds;
   • If no timezone is specified, your local timezone is assumed.

3. To reset the input:

   • Click “Clear” to remove the input and the result.

2.3 Using the current time

1. Click “Use current time” at the top:

   • The left timestamp input will be filled with the current Unix timestamp (in seconds);
   • The right date/time input will be filled with the current date/time;
   • All result cards and world time entries refresh accordingly.

2. You can then adjust either side and re‑run the conversions.

3. What is a Unix timestamp and where is it used?

3.1 A simple explanation of Unix timestamps

• Seconds or milliseconds since 1970‑01‑01 00:00:00 UTC

  • Second‑based timestamps are usually 10‑digit integers;
  • Millisecond‑based timestamps are usually 13‑digit integers.

• Timezone‑agnostic representation of a moment
  The timestamp itself does not contain timezone information. Only when you format it as a date/time do timezones come into play.

• Widely used in servers, databases, and logs
  It is a common, compact way to store and compare time values.

3.2 Typical use cases

• API signatures and anti‑replay protection
  Many APIs include a timestamp field in requests. You can use this tool to verify that the timestamp matches the expected moment.

• Log analysis and monitoring alerts
  Logs and monitoring systems often show timestamps instead of formatted dates. Converting them makes it much easier to understand when an event occurred.

• Scheduling tasks and expiration times
  CRON jobs, cache expirations, and time‑based business rules frequently rely on Unix timestamps for comparison and calculations.

4. Common issues and troubleshooting

4.1 The converted time looks wrong

• Seconds vs. milliseconds mismatch

  • A 13‑digit value is usually in milliseconds; treating it as seconds will give you a date far in the future;
  • A 10‑digit value is usually in seconds; treating it as milliseconds will push it back toward 1970.

• Local time vs. UTC confusion

  • The display mode (Local / UTC) changes how formatted results and world times are shown;
  • When comparing with backend values or documentation that use UTC, make sure you are in UTC mode.

• Unparsable date/time string

  • Check that the format matches the examples shown in the placeholder and help text;
  • Ensure hours, minutes, and seconds are present;
  • Verify that the timezone part (such as +08:00) is correctly written if you include one.

4.2 Why does the same timestamp show different times on different systems?

• Different timezones

  • A Unix timestamp represents a single instant in time, but when it is formatted, local timezone rules are applied;
  • For example, 2024-01-01 08:00:00 in Beijing and 2024-01-01 00:00:00 in UTC represent the same timestamp.

• Daylight saving time
  Regions with daylight saving time may shift clocks by one hour seasonally, so the same timestamp can appear as different local times across DST boundaries.

5. Tips for efficient use

• Verify timestamps when debugging APIs
  Paste the timestamp field from an API request or response into the converter to confirm it matches the intended time window.

• Use the world time view for cross‑region debugging

  • When dealing with users or servers in multiple regions, the world time section helps you quickly see the corresponding time in major cities;
  • This is especially helpful when investigating incidents that involve teams in different timezones.

• Standardize on a small set of date/time formats

  • Prefer formats like YYYY-MM-DD HH:mm:ss or ISO‑8601 strings;
  • Agreeing on one format between frontend and backend reduces parsing errors.

• Bookmark it as an “online Unix timestamp converter”
  You can easily find this page with queries like “timestamp converter”, “Unix timestamp to date”, “date to timestamp”, or “online Unix time tool”. Adding it to your bookmarks makes everyday debugging much faster.

Summary:
This online timestamp converter helps you quickly transform values between Unix timestamps and human‑readable date/time formats, while also showing corresponding times in multiple cities. All calculations run locally in your browser, making it safe and convenient for everyday development and operations.