DevEquiv

    Java DateTimeFormatter to Python strftime() Converter

    Paste a java.time.format.DateTimeFormatter pattern to get the equivalent Python strftime() format.

    Token-by-token mapping

    Shown one token at a time — some dialects combine two adjacent tokens (like a day number plus an ordinal suffix) into a single result above, which can differ slightly from this per-token view.

    Requires review

    Java DateTimeFormatter
    yyyy-MM-dd'T'HH:mm:ss
    Python strftime()
    %Y-%m-%dT%H:%M:%S

    Main limitation: Java's single `d` (day without leading zero) has no strftime equivalent — standard strftime only supports zero-padded `%d`.

    How it differs

    • Java's single d (day without leading zero) has no strftime equivalent — standard strftime only supports zero-padded %d.
    • Java's single-quote literal syntax ('T', '' for a literal quote) is unwrapped to plain text before being escaped for strftime (where only % needs escaping, as %%).
    • Java's SSSSSS (6-digit fraction) maps to strftime's %f; Java's SSS (3-digit milliseconds) has no strftime equivalent since Python's %f is always microseconds.

    Examples

    ISO-8601 timestamp

    Java DateTimeFormatter yyyy-MM-dd'T'HH:mm:ss
    Python strftime() %Y-%m-%dT%H:%M:%S

    The quoted literal `'T'` becomes plain `T` text in the strftime output.

    Non-padded day (partial conversion)

    Java DateTimeFormatter EEEE, MMMM d, yyyy
    Python strftime() %A, %B , %Y

    Java's `d` (day without leading zero) has no strftime equivalent and is dropped with a warning, leaving the day number missing from the output.

    Edge cases

    Edge case

    EEEE, MMMM d, yyyy loses its day number entirely when converted, because Java's non-padded d has no strftime counterpart — the output reads "Monday, July , 2026" and a warning flags the gap.

    Edge case

    Java's era (G), nano-of-second (n/N), and locale-dependent weekday (e/c) patterns are all left unmapped rather than approximated.

    References

    • Java SE docs — DateTimeFormatter (v21) — checked 2026-07-29
    • Python docs — strftime() and strptime() format codes (v3.x) — checked 2026-07-29

    Last verified 2026-07-29.