Unix タイムスタンプ変換
Unix エポック（秒/ミリ秒）と日時を相互に変換。
Unix タイムスタンプ（秒/ミリ秒）を貼り付けて UTC、ローカル、ISO 8601、RFC 2822 を表示。日時から Unix タイムスタンプも生成できます。
現在時刻
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— —
タイムスタンプから
UTC
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ローカル
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ISO 8601
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RFC 2822
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相対
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日時から
秒
— ミリ秒
— What is a Unix timestamp?
A Unix timestamp (also called an epoch timestamp) is the number of seconds that have elapsed since 00:00:00 UTC on 1 January 1970 — the Unix epoch — not counting leap seconds.
For example, 1700000000 corresponds to 14 November 2023 22:13:20 UTC. Because it is a single number, a Unix timestamp is compact and timezone-independent, which is why databases, logs, and APIs use it so widely.
Milliseconds since the epoch (seconds multiplied by 1,000) are also common in JavaScript, browsers, and mobile apps. This tool converts between these representations and human-readable dates in both directions.
Key features
- Seconds and milliseconds support
- UTC, local, ISO 8601, RFC 2822 and relative time
- Live current-time display
- Convert both ways (timestamp ↔ date)
- Runs 100% in your browser
- Timezone-aware local conversion
Privacy guarantee
All conversions happen locally in your browser. Timestamps and dates you enter are never transmitted to any server, never stored, and never logged.
How to convert a timestamp
- 1
Enter a timestamp
Paste a Unix timestamp in seconds or milliseconds into the input box.
- 2
Read the results
See the instant conversion to UTC, local time, ISO 8601, RFC 2822, and a relative time.
- 3
Convert back from a date
Use the date picker to turn any date and time into a Unix timestamp.
Frequently asked questions
What is the Unix epoch?
The Unix epoch is 1 January 1970 00:00:00 UTC — the reference point from which Unix timestamps are counted.
How do I convert a timestamp to a date?
Paste the timestamp into the converter. If you use JavaScript, multiply a seconds timestamp by 1,000 to pass it as milliseconds.
What is the difference between seconds and milliseconds?
A milliseconds timestamp is simply the seconds value multiplied by 1,000. Both represent the same instant.
Is a Unix timestamp affected by time zones?
No. A Unix timestamp is a single UTC-based number; the local time is only different when displayed for a specific time zone.
What is the Year 2038 problem?
On 32-bit systems, seconds-based Unix timestamps overflow on 19 January 2038. Modern 64-bit systems avoid this issue.
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