BASIC Playground

Write or paste a vintage-style BASIC program and run it. This is the same interpreter that runs the BASIC games on this site.

Program (line numbers required)

Load:

Language notes

Statements: PRINT (with TAB, SPC, , and ;), INPUT, LET, IF…THEN, GOTO, GOSUB/RETURN, ON…GOTO/GOSUB, FOR/NEXT/STEP, DIM, READ/DATA/RESTORE, DEF FN, REM, STOP, END.
Functions: ABS ATN COS EXP INT LOG RND SGN SIN SQR TAN and LEFT$ RIGHT$ MID$ LEN STR$ VAL CHR$ ASC.
Extras not in the old books: CLS clears the screen, PAUSE n waits n milliseconds.
Numbers print the classic way (leading space for the sign). Comparisons give -1 for true and 0 for false. Text typed into INPUT is upper-cased.
Programs run entirely in your browser. Nothing you type here is sent anywhere or saved.

Listings for each BASIC game are in the Load menu, so you can read them, change them and run your changes.