Date, Time & ID
Calculate and convert dates and times, and generate identifiers such as UUID and ULID. Includes Unix time conversion and Japanese era conversion.
9 tools・Ordered by measured page views over the last 90 days.
UUID Generator
Generate v4 UUIDs in bulk with a secure RNG. Options for uppercase, no hyphens, and braces.
Date Difference Calculator
Show the difference between two dates and times as a Y/M/D H:M:S breakdown plus totals in each unit.
Unix Time Converter
Convert between Unix timestamps and dates: seconds/ms, time zone and ISO 8601.
UUID Generator (v4 / v7)
Bulk-generate random v4 and time-ordered v7 UUIDs with count and format options. Copy or save as text. Runs in-browser.
Japanese Era (Wareki) Converter
Convert between Reiwa, Heisei, Showa, Taisho, Meiji and the Gregorian calendar. Era-change boundary dates are judged by exact date.
Cron Expression Parser
Explain a cron expression and compute the next run times. Supports weekdays, steps, ranges, and @daily macros.
ULID Generator
Bulk-generate 128-bit, time-sortable unique IDs (26-char Base32) as a UUID alternative. Cryptographic RNG, count and copy support.
Age Calculator
Get the exact age from a date of birth and reference date. Also shows kazoe age, days lived and days until the next birthday.
Time Zone Converter
Enter a date and time and see it as local time in major cities worldwide, with daylight saving time detected automatically.