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ISO 8601 and RFC 3339 Formatter

Convert safely between Unix, ISO 8601, RFC 3339, and human-readable inputs without guessing whether the value is local or UTC.

Direct Answer

ISO 8601 and RFC 3339 are safest when the value includes an explicit timezone offset or `Z` suffix. This formatter lets you parse, normalize, and batch-convert those values before they turn into silent timezone bugs.

Server-rendered worked result

2026-07-21T17:30:00.000Z converts to Unix 1784655000

UTC
2026-07-21T17:30:00+00:00
America/New_York
2026-07-21T13:30:00-04:00
Europe/London
2026-07-21T18:30:00+01:00
Asia/Tokyo
2026-07-22T02:30:00+09:00
JavaScript
new Date().toISOString()
Python
datetime.now(timezone.utc).isoformat()
Go
time.Now().Format(time.RFC3339)
Rust
Utc::now().to_rfc3339()