0…9−. bkspdel space venter tab =` z … Help
Stopwatch: [ start,
\ lap, ] total 
set1
2
units × dates tz chars … currency 
→ today

• It's just one html page. With
good ol' table design and big seemefromafar letters. Well, digits.
• The digits, dot and minus keys enter the number to convert.
• The space clears the input.
• Backspace and Del remove the last digit/dot (backspace doesn't work if you have
a "previous" page in the browser history).
• Letters 'pntefdckTEFDCKri' modify the value. Try and see.
• No other editing means are available (except the evaluator). Z is undo!
• Control+V or just V or simply Enter paste the clipboard contents (if it's a number)
into the converter.
• The Tab key swithes between two sets of convertions/calculations.
• Keys ` and = ask for a math expression and evaluate it.
• The evaluator (aka calculator) is just the javascript eval function with some
syntactic sugar: pi, PI, e, E, LN2, LN10, SQRT2 are the constants,
sqrt, log,
exp, pow,
sin, cos, tan, asin, acos, atan,
abs, min, max, floor, ceil,
round, random are functions. Some have one letter abbrevs. Numbers may be
in degrees (@ after the number), and such numbers are converted into radians.
360@ = 2*π.
• Factorization of big numbers may take long time. E.g. testing for primeness of 100000000000031
(that's 10^14+31) takes about 30 seconds or PIV 1.8 GHz.
• The calendar is 'borrowed' from the Google applets.
• If the input number looks like a date (D, DD, MDD, MMDD, YMMDD, YYMMDD, YYYYMMDD),
the week day and the distanse to that date are calculated.
Years 0..39 are considered in the XXI century, 40..99 — in the XXth.
• Stopwatch has clearstart ([), showelapsedtime (]) and storelaptime (\) functions.