For simple calculations when using a computer I suggest: http://speedcrunch.org/ http://speedcrunch.org/ For things with units: https://frinklang.org/ https://

For simple calculations when using a computer I suggest: http://speedcrunch.org/ http://speedcrunch.org/ For things with units: https://frinklang.org/ https://frinklang.org/ Since learning of it on hackernews a few months ago I find I use it frequently.