Date Format Detective

You have Fri, 12 Jun 2026 10:30:00 +0300 and need the format string that produces it — in whatever language today’s codebase happens to be. Paste the date string; the detective reverse-engineers the pattern for six ecosystems at once. Best-effort heuristics: always double-check ambiguous day/month order.

Date string

Examples:

Cross-language token cheat sheet

Component	strftime	PHP	Moment/Day.js	Java	Go	.NET
Year, 4-digit	%Y	Y	YYYY	yyyy	2006	yyyy
Year, 2-digit	%y	y	YY	yy	06	yy
Month 6	%-m†	n	M	M	1	M‡
Month 06	%m	m	MM	MM	01	MM
Month Jun	%b	M	MMM	MMM	Jan	MMM
Month June	%B	F	MMMM	MMMM	January	MMMM
Day 2	%-d†	j	D	d	2	d‡
Day 02	%d	d	DD	dd	02	dd
Day 2nd	—	jS	Do	—	—	—
Weekday Fri	%a	D	ddd	EEE	Mon	ddd
Weekday Friday	%A	l	dddd	EEEE	Monday	dddd
Hour 9 (24h)	%-H†	G	H	H	—	H‡
Hour 09 (24h)	%H	H	HH	HH	15	HH
Hour 9 (12h)	%-I†	g	h	h	3	h‡
Hour 09 (12h)	%I	h	hh	hh	03	hh
Minute 05	%M	i	mm	mm	04	mm
Second 05	%S	s	ss	ss	05	ss
Millisecond 123	%f (µs)†	v	SSS	SSS	.000	fff
AM / PM	%p	A	A	a	PM	tt
Offset +03:00	%:z†	P	Z	XXX	-07:00	zzz
Offset +0300	%z	O	ZZ	Z	-0700	—
Zone abbr. EEST	%Z	T	—	z	MST	—
Unix seconds	%s	U	X	—	—	—

† glibc/BSD extension — on Windows strftime use %#d-style flags; Python supports %-d on Linux/macOS only. ‡ in .NET a single-character format string means a standard format; use %M or embed it in a longer pattern. Java tokens are for DateTimeFormatter (SimpleDateFormat differs in zone/era handling).