How do you type Unicode characters using hexadecimal codes?

harrymc's answer is good, providing you're able/allowed to change the registry settings.

If not, you can use the Windows Calculator Accessory to convert from hexadecimal to decimal. The default mode won't do this: XP and Vista have a "Scientific mode, whereas Windows 7, 8, 8.1 and 10 have a "Programmer" mode.

Select Hex base, and then type in your hexadecimal number. Then change to Dec base to see the equivalent value in decimal. That's the number you need to type into your numeric keypad while holding down the Alt key.

This might depend on the input language, and you might need to prefix a zero to the decimal value.

Found this in How to enter Unicode characters in Microsoft Windows :

I tested this on Windows XP and Windows 2003. This method works regardless of any of your language settings, but is the most cumbersome to type:

1. Press and hold down the Alt key.
2. Press the + (plus) key on the numeric keypad.
3. Type the hexidecimal unicode value.
4. Release the Alt key.

Alas, this appears to require a registry setting. It was already set on my computer, but some readers report that this method didn't work for them, and this is probably why. If you don't know what the registry is, please don't try this. Under HKEY_CURRENT_USER\Control Panel\Input Method, set EnableHexNumpad to "1". If you have to add it, set the type to be REG_SZ.

You should log off then log on after this registry change, or even reboot.

On Mac OS X: open International in System Preferences, and in Input Menu select "Unicode Hex Input" to add this option to the input menu. Sounds obvious, but this is well hidden in the long list of languages, between Ukrainian and Vietnamese. When selected, hold down Option and type the 4 digit hex code.

Also on OS X: Calculator can be set to Programmer mode (Cmd-3), which allows for entering decimal, octal and hexadecimal codes, which are then displayed as ASCII or Unicode. However, Copy will give one the code, not the character equivalent(s). Anyone?

(For Windows, see How to enter Unicode characters in Microsoft Windows; for other input methods see Wikipedia.)

And here on Super User:

• Insert Unicode characters via the keyboard?
• Typing strange letters ¿w/o numpad?
• How to type special characters in Linux?

And to go into extremes:

• How do I create Unicode smilies like ٩(•̮̮̃•̃)۶

In Ubuntu (and variants thereof, like LinuxMint) you can enter Unicode values by pressing Ctrl+Shift+u followed by the Unicode value and Enter, for example:

Ctrl+Shift+u 263a then Enter yields:

Text: ☺
Screenshot:

You might be able to couple this with AutoHotkey for easier input, or possible input in Windows.