Windows
Hold Alt and type 7686 on the numeric keypad.
Accents
Copy the character, or use the shortcut that matches your keyboard and app.
All B accentsHold Alt and type 7686 on the numeric keypad.
Character Viewer → b line below
Type 1E06 then Alt + X
Insert → Special characters → B line below
Click the keycap, then paste with Ctrl+V or Cmd+V.
Num Lock on, hold Alt, type 7686, release Alt.
Use the Unicode, HTML, CSS, or JS value below in documents and stylesheets.
U+1E06ḆḆ\1E06\u{1E06}Alt + 7686