WhatDayIsIt - Date Highlighter & Day Finder

Instantly see what day any date falls on. Highlights dates on any webpage - hover to see Monday, Tuesday, etc.

See which weekday a date falls on without opening a calendar. WhatDayIsIt highlights valid dates in webpage text and shows the weekday when you hover over the calendar icon. FEATURES • Automatic detection of supported dates in webpage text. • Hover over the calendar icon to see Monday, Tuesday, and the other weekdays. • A toolbar badge shows how many dates were found in each tab and updates as page content changes. • Supports ISO dates, numeric formats, English month names and abbreviations, Polish month names, and relative words such as today and tomorrow. • Recognizes English and Polish date text according to the page language. • Turn the extension on or off across tabs, show or hide date highlighting, and place the calendar icon before or after each date. • Handles dynamically loaded page content. DATE FORMATS Examples include December 25, 2026; Dec. 25, 2026; 25/12/2026; 25.12.2026; 2026-12-25; and 25 grudnia 2026. For ambiguous numeric dates, Polish pages use day/month order and English pages use month/day order. Dot-separated dates use day/month order. Impossible calendar dates are left unchanged. PRIVACY Date recognition runs locally in your browser. The extension does not collect page content or browsing history and does not use analytics or tracking. Only your enabled state, highlighting preference, and icon position are stored using Chrome Storage Sync; Chrome may synchronize these preferences according to your Chrome Sync settings. NEW IN VERSION 1.4 Per-tab date counts, more reliable calendar-date validation, safer handling of original page text, and consistent settings across open tabs. Open source: https://github.com/Fajkowsky/WhatDayIsIt