Date Diff Calculator

Unix Timestamp ↔ Date

Convert Unix time to a date and back, with support for arbitrary (IANA) time zones.

Cron Parser

Parse a cron expression (5 or 6 fields, including @-shortcuts) — a plain-language schedule description and next run times in a chosen time zone.

Number Base Converter

Convert between binary, octal, decimal, hexadecimal, and any arbitrary (2-36) base — enter a number into any field.

Bitwise Operations

AND/OR/XOR/NAND/NOR/XNOR/NOT and shifts on integers of a given width (8/16/32/64 bits) in any number base.

Age Calculator

Exact age from a birth date — years/months/days, total time lived, and the next birthday.

Timezone Converter

One moment in time, across several time zones at once. Compare working hours, plan calls, see the day difference.

Basic Auth Generator

Generate or decode an HTTP Basic Authentication header — Base64(username:password).

Placeholder Image Generator

Generate a placeholder image of a given size for mockups and layout.

Cookie Parser

Parse a Set-Cookie header or a Cookie/document.cookie string into name, value, attributes, and a check for common security mistakes.

UUID Generator

Generate UUID versions 1, 3, 4, 5, 6 and 7 — random, time-based, and name-based.

Color Converter

Convert colors between HEX, RGB, HSL, HSV/HSB, and CMYK — enter a value into any field and the rest update instantly.

ROT13 / Caesar Cipher

Caesar cipher — a cyclic shift of Latin alphabet letters. ROT13 is the special case with shift 13 (button below), symmetric: encode and decode give the same result. Other characters (digits, punctuation, non-Latin letters) are left unchanged.