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Subscription plans

3-days subscription

from $0.95 / day

total cost for 3 days $2.85

Monthly subscription

from $0.15 / day

total cost for one month $4.50

Annual subscription

from $0.05 / day

total cost for one year $18.25

By subscribing you are directly supporting this project. I am very thankful for all of you that subscribe and show your appreciation of my work through selecting one of subscription plans.
You can select one of three available subscription plans. Select the plan that you think will be the most cost-effective for your job. With flexible term lengths, you can get exactly the service you need for as long as you need it. With one subscription plan you can use calculator at your work, at your home or when traveling.

Flexible term lengths

With 3-day subscription plan you can try full service without making big up-front investment. Once you see that full service meets your needs, continue with monthly subscription. When you find that full service becomes your every day routine select annual subscription and save big on low cost/long term subscription plan.

Subscription benefits

When you subscribe you will have instant access to all available services for all available calculator deployments:
  • online web calculators
  • web start calculators
  • calculator available for download
  • calculator for android smart phone
Calculator availability for each deployment depends on the current development stage. For every single available calculator you can check on its introduction page what deployments are currently available, or you can check it on the deployments page.

System requirements

Internet connection is required for any calculator to work. Regardless of you computer system it should be possible to use at least one of available deployments. Depending on the available and preferred deployment, system requirements are as follows:
  • online web calculators - web browser with Javascript support
  • web start calculators - JavaTM 1.8+ for your computer
  • calculator available for download - Windows 64bit
  • calculator for android smart phone - name tells it all

Subscription renewal

Your subscription will not automatically renew and you will not be charged recursively. Once your subscription expires, you will have to renew it manually.

Subscription canceling and refunding

You can request to be refunded for any subscription plan. For annual subscription plan, please send me your request within 30 days from purchase. After receiving your refund request I will respond you within reasonable time.

Payment options

At this moment you can pay and have immediate access to calculators using PayPal or using 2Checkout payment processing service. If you prefer other kind of payment, please contact me and I will respond in shortest possible time, but you will have to be patient as the whole process of other payment option can take some time.

Detailed service agreement

Read more about service terms for calculators on this web site at Software as a service agreement page.