UNIX Timestamp Converter

Tool Introduction

The UNIX Timestamp Converter is an efficient and convenient online tool designed to help users perform two-way conversions between Date/Time and UNIX timestamps. It supports converting any specified date and time to a UNIX timestamp in seconds or milliseconds, and vice versa. Whether for development debugging, data analysis, or daily time queries, this tool provides fast and accurate conversion services.

Origin and Use of UNIX Timestamps

A UNIX timestamp, also known as POSIX time or Epoch time, is the number of seconds or milliseconds that have elapsed since 00:00:00 UTC (Coordinated Universal Time) on January 1, 1970, disregarding leap seconds. It is an integer value widely used in computer systems, databases, network protocols, and other fields to represent and record points in time. Due to its simplicity, global uniformity (based on UTC), and ease of calculation, the UNIX timestamp is one of the preferred ways to handle and store time information.

• Origin: Originated from the UNIX operating system, where an integer was used internally to efficiently manage and record time.
• Uses:
• Data Storage: Storing time in databases for easy sorting and cross-timezone processing.
• API Interfaces: When exchanging time data between different systems, UNIX timestamps are often used to avoid timezone and format issues.
• Logging: Marking event occurrence times in log files for easy tracing and analysis.
• Time Calculation: Convenient for performing time addition and subtraction, such as calculating time intervals.

How to Use

1. Date to UNIX Timestamp:
   • In the "Date" input box, select or manually enter the date and time you need to convert (defaults to current local time).
   • In the "Type" option, select the timestamp unit you want to generate: "Seconds" or "Milliseconds".
   • The "Timestamp" input box will display the converted UNIX timestamp in real-time.
2. UNIX Timestamp to Date:
   • In the "Timestamp" input box, enter the UNIX timestamp you have.
   • In the "Type" option, select the unit of the timestamp you entered: "Seconds" or "Milliseconds".
   • The "Date" input box will display the converted date and time in real-time.

Input Parameter Format and Requirements:

• Date: Uses datetime-local format, for example: 2023-10-27T10:30. Usually accurate to the second; if more precise millisecond conversion is needed, it is recommended to directly input a millisecond timestamp for reverse operation.
• Timestamp: Pure numbers, integer format. Second-level timestamps are usually 10 digits, millisecond-level timestamps are usually 13 digits.
• Type: Must select "Seconds" or "Milliseconds" to ensure correct conversion precision.

Output Result Format:

• Date: Output as a local format date and time string, for example: 2023-10-27T10:30:00.
• Timestamp: Output as a pure number (integer), representing the number of seconds or milliseconds since January 1, 1970.

Usage Examples

The following examples are demonstrated based on the local timezone UTC+8:

• Example 1: Date to Second-level UNIX Timestamp
  • Operation: Enter 2023-10-27T10:30:00 in the "Date" box, select "Type" as "Seconds".
  • Expected Output: "Timestamp" box displays 1698373800.
  • Explanation: Local time 2023-10-27 10:30:00 (UTC+8) corresponds to UTC time 2023-10-27 02:30:00, whose second-level timestamp is 1698373800.
• Example 2: Date to Millisecond-level UNIX Timestamp
  • Operation: Enter 2023-10-27T10:30:00 in the "Date" box, select "Type" as "Milliseconds".
  • Expected Output: "Timestamp" box displays 1698373800000.
  • Explanation: Multiply the second-level timestamp by 1000 to get the millisecond-level timestamp.
• Example 3: Second-level UNIX Timestamp to Date
  • Operation: Enter 1698373800 in the "Timestamp" box, select "Type" as "Seconds".
  • Expected Output: "Date" box displays 2023-10-27T10:30:00.
  • Explanation: Convert the second-level timestamp back to local date and time.
• Example 4: Millisecond-level UNIX Timestamp to Date
  • Operation: Enter 1698373800000 in the "Timestamp" box, select "Type" as "Milliseconds".
  • Expected Output: "Date" box displays 2023-10-27T10:30:00.
  • Explanation: Convert the millisecond-level timestamp back to local date and time; the date input box usually only displays up to seconds.

Frequently Asked Questions

• Q: What is a UNIX timestamp? A: A UNIX timestamp is the number of seconds or milliseconds that have elapsed since 00:00:00 UTC/GMT on January 01, 1970 (midnight), disregarding leap seconds. It is a standard method for representing time in computer systems.
• Q: Which timestamp units are supported? A: This tool supports converting date and time to UNIX timestamps (seconds or milliseconds), and also supports converting UNIX timestamps (seconds or milliseconds) back to date and time.
• Q: Does timestamp conversion consider timezones? A: The "Date" input box of this tool is for local date and time (datetime-local), meaning you enter the local time of your current operating system. The conversion results will be calculated and displayed based on your browser's or operating system's local timezone. For example, if you enter local time, it will first be converted to UTC time, and then the UNIX timestamp will be calculated; the reverse conversion works similarly.
• Q: When converting a millisecond timestamp to a date, why is the date only accurate to seconds? A: The datetime-local input box in most browsers usually only displays accuracy up to seconds. When you enter a millisecond timestamp and convert it to a date, although milliseconds may be processed internally, the display will truncate or ignore the millisecond part, only showing up to seconds.

Notes

• Date Format: Please ensure that the format entered or selected in the "Date" input box is a valid local date and time format (e.g., YYYY-MM-DDTHH:MM:SS). Incorrect formats may lead to conversion failure or incorrect results.
• Timezone Settings: Conversion results will be affected by your browser's or operating system's local timezone settings. If you need to handle conversions for a specific timezone, please ensure your system's timezone settings are correct, or perform manual timezone adjustments.
• Timestamp Precision: The datetime-local input box is usually only accurate to seconds. If you need to convert a date to a timestamp with millisecond precision, this tool will default the millisecond part to 000. For millisecond precision, it is recommended to directly input a millisecond timestamp for reverse conversion.
• Timestamp Range: UNIX timestamps are usually represented by 32-bit or 64-bit integers, which have representation range limitations. Date and time values outside this range (such as the very distant past or future) may not be converted correctly.