Please have a look at another scientific application of mine :



Sometimes I also make stupid things:



Or not :




Visitor book

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17/01/2024 7:35:26

Oakland, California, USA

Anonymous wrote :


23/03/2023 10:49:26


Tim Murphy wrote :

A truly fantastic calculator on so many levels.

Many, many thanks for this. Wonderful!

10/11/2022 9:25:35

Tokyo, Japan

Esa wrote :

What a wonderful piece of software! I'm glad to see that there are people who actually remember to use computers for the purpose of computation - and help others do so as well!

11/03/2022 19:21:42


Matt wrote :

just started to use Chalk and am fascinated by the choices you've made. However, the UI is very small on my large monitor. Is there any way you could add an option to scale the UI and output? I'd love to be able to double up the size of the UI. Many apps use cmd and -/+ to scale the window. I'm on a 4K monitor and virtually every other app I use scales to use the High-DPI output option. Thanks!

10/03/2022 3:14:30

Toronto, Canada

H B Acharya wrote :

It takes a great deal of patient thought to make something simple and usable. I am a happy user.

Many years ago, as a student, I first learned about interval arithmetic, accuracy, and representation from the work of Bill Walster at Sun (before it got eaten by Oracle).

Your article explaining the shortcoming of modern calculators and your careful design of Chalk, reminded me of this. Merci beaucoup, not only for beautiful software, but also beautiful thoughts!

06/06/2020 16:35:02

France, Nancy

Jmi wrote :

A gem, nothing,to add.
I have been roaming the web for such an application, very handy, very precisely designed, highly recommended for casual as well as pro users, thanks a lot Pierre for this beautiful piece of hard work !!!
No need to tell, I adopted it for my daily developper job.

27/04/2020 14:32:03

Toulouse, France

Laurent wrote :

Chalk is a wonderful application. I use it every day. Very convenient.
Many thanks to Pierre who is very fast to take into account modifications / improvements suggestions.

21/03/2020 23:00:55

Santa Barbara, CA USA

Deborah wrote :

Chalk is wonderful. Thank you, Pierre!

30/08/2019 18:55:25


Clark Dunson wrote :

Hello Pierre;
My new company won't buy me Matlab, so I'm with Chalk. Love it.

25/04/2018 15:31:40


Martin wrote :

Love Chalk, it is the desktop calculator I have been looking for!

20/03/2018 21:12:58

San Francisco, CA

Pratik wrote :

Thanks for your hard work!

08/02/2018 22:02:50

Utilisateur wrote :

Ça marche plutôt très bien !

27/04/2017 7:04:42


Jeff wrote :

Pierre, this is very impressive.

14/04/2017 4:11:15

USA, Boston

Prashant wrote :

Chalk is a great interface! I love that it can handle complex numbers and graphs

29/07/2013 23:24:22

France, Burgundy

Pierre Chatelier wrote :

Livre d'or ouvert !
Visitor book open !


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