Time/Numbers
Find the ISO 8601 week number for a date, or find the start/end dates of a specific week.
Convert Unix time to a date and back, with support for arbitrary (IANA) time zones.
Parse a cron expression (5 or 6 fields, including @-shortcuts) — a plain-language schedule description and next run times in a chosen time zone.
Convert between binary, octal, decimal, hexadecimal, and any arbitrary (2-36) base — enter a number into any field.
AND/OR/XOR/NAND/NOR/XNOR/NOT and shifts on integers of a given width (8/16/32/64 bits) in any number base.
Exact difference between two dates/times — calendar breakdown (years, months, days…), total duration, and business day count.
Exact age from a birth date — years/months/days, total time lived, and the next birthday.
Flatten nested JSON into a flat "path: value" list, and rebuild it back into a nested structure (Unflatten). Path notation matches JSONPath/JSON Diff: store.book[0].price.
Escape text into a string literal (quotes, backslash, control characters) for pasting into code, or unescape it back.
Real-time text statistics: characters (with and without spaces), words, lines, sentences, paragraphs, and size in bytes (UTF-8).
Explain step by step whether the browser will allow a cross-origin request — simple/preflight classification, Access-Control-* response header checks, and a verdict.
Convert colors between HEX, RGB, HSL, HSV/HSB, and CMYK — enter a value into any field and the rest update instantly.
Base32 (RFC 4648) encode and decode — text and files, right in your browser.