Free, compact, capable tape calculator. This expression evaluator processes complex expressions like \"-ln(1+2)*3% + sin(4 5\\6)^7 to hex\" and allows exact rational values like 2 1\\3 instead of 2.3333... Compact single-line mode or flexible multi-line editor to edit past work, recalculate, cut and paste on the tape, save to file, restore. Select font, button size. Show/hide buttons. Number bases: binary, octal, hexadecimal. Group digits. Help.