Keyboard map

Hold Option (Alt) for the large character. Add Shift for the small character above it. The small label at the bottom is the ordinary key. Option-Shift-1–9 types ¹²³⁴⁵⁶⁷⁸⁹ and Option-Shift-Minus types ⁻ where those chords are free. Option-Shift-0 remains ⍬. In the browser, Option-Shift-3 remains #; use the superscript dead key for ³.

⋄`

¹¨1

²⌽2

³√3

⁴⇄4

⁵₅5

⁶⁶6

⁷∆7

⁸∞8

⁹∨9

⍬∧0

⁻¯-

≠≡=

Delete

Tab

⎕q

⍵w

∊e

⍴r

∘t

•y

÷u

⍳i

○o

πp

[

]

⍭\

Caps

⍺a

⌈s

⌊d

∂f

∇g

←h

↓j

↕↑k

↦l

⁝⊣;

⊢'

Enter

Shift

⊂z

⊃x

∩c

∪v

⊥b

⊤n

×m

≤↢,

≥↣.

≢¿/

Shift

Ctrl

Opt

Cmd

Space

Cmd

Opt

Ctrl

Orange borders mark dead keys. You can hold or release Option between keys. Holding it through 5x51 enters ₓ₁. Repeat the prefix key, or press Space, to enter the dead key’s own character. Follow-ups can be sequences, such as -1 for a negative superscript or subscript.

Key	Double-tap	Follow-ups
1	¨	t:⍤; o:⍥; g:⍢; 8:⍣; `:⍨
5	₅	0–9:₀–₉; x:ₓ; j:ⱼ; e:ₑ; r:ᵣ; h:ₕ; s:ₛ; p:ₚ; -0–9:₋₀–₋₉
6	⁶	0–9:⁰–⁹; -0–9:⁻⁰–⁻⁹; b:ᵇ; t:ᵀ; u:ᵘ
-	¯	,:⍪; \:⍀; /:⌿; a:⍶; w:⍹; 7:⍙; `:⍚; 0:⊼; 9:⊽; e:⍷; i:⍸; z:⊆
q	⎕	t:⌻; =:⌸; u:⌹; `:⌺; ;:⍠; \:⌷
o	○	-:⊖; \:⍉; /:⊘; m:⊗; u:⨸; 8:⍟; c:⍝; b:⍎; n:⍕
\	⍭	7:⍋; g:⍒

This is the US-based map used in the browser and REPL, and by the native BasedPL-us macOS layout. Regional macOS layouts preserve their native Option characters and move conflicting BPL shortcuts. See macOS installation.

macOS installation

After pip install basedpl, run basedpl-install to install the Jupyter kernel, SAX2B and BQN386B fonts, and the US keyboard layout for your user. Pass uk, de, fr or es for British, German QWERTZ, French AZERTY or Spanish: for example, basedpl-install de.

In System Settings, open Keyboard → Text Input → Edit, add BasedPL-us (or your chosen code), then select it from the input menu. If the layout isn’t listed, log out and back in. editors/macos/BasedPL-{code}.txt lists each native layout’s shortcuts. On Linux, basedpl-install installs the kernel and fonts without a native keyboard layout.