About this site
The site mainly started around the idea of an online generator of exercises to practice the soroban. It evolved a bit with the addition of pages with mental calculation software; then the virtual soroban and its "tutorials" and the possibility to get an operation being displayed on the virtual soroban. A forum was needed to overcome the limitation of disqus, which is a great commenting system anyway.
Donations welcome
Since we changed hosting in August 2021 to use pythonanywhere.com, we are now billed 6€ per month. This is without counting for the domain name cost which is about 19€ per year. The total cost is then around 90€ per year.
Any donation is welcome to cover those recurring costs. I will also take them as a tip for the work I made on this site. We thank any donor in advance for their good gesture.
- Total donation received for 2023 so far: 10€.
You may need a currency converter from/to €, you could give a try to the one at xe.com. Beware that Paypal does not use the same exact exchange rate that xe.com
Buy me a coffee instead ?
ko-fi.com
May be you want to buy me a coffee instead ? Go to my ko-fi page.
In fact, you will be able to change the amount of your donation, if you wish to.
Bitcoins accepted here
We are now accepting donations in bitcoins.
You can either use the new Bech32 SegWit address ::bech32::. This is the preferred method.
However, for backward compatibility, we provide also a P2SH address ::p2sh::
Technologies

We are now accepting donations in bitcoins.
You can either use the new Bech32 SegWit address ::bech32::. This is the preferred method.
However, for backward compatibility, we provide also a P2SH address ::p2sh::
This is what is used to create this site
The last revision of the code of the site has the git HEAD commit id e976ba5
Cookies
We use cookies on this website. You can read our cookie policy on this page.