Terms of use
Last updated November 1, 2026.
These terms cover this website, the free notice-by calculator and spreadsheet, and the Duespan app at /app/, provided by Montgomery Appworks LLC, 9905 S Pennsylvania Ave Ste A, Oklahoma City, OK 73159.
Not legal advice
The calculator subtracts the notice period you enter from the renewal date you enter. It can't read your contract. Contracts differ in how they count days and how notice must be given, so your contract's wording decides your real deadline. Check it, and ask a lawyer if you're unsure.
No warranty
The site, calculator and spreadsheet are provided free and "as is", without warranties of any kind. To the fullest extent the law allows, we aren't liable for losses from using them, including a missed notice deadline.
Example data
Comparisons marked EXAMPLE are made up for illustration and don't describe any real vendor, plan or price.
Accounts
The app is free. It may change or be paused. You're responsible for your password and for who you give your organization's invite code to; anyone with the code can join and see and edit your organization's equipment and contracts. Calendar reminders are .ics files you download. For an auto-renewing contract the file includes all-day events 120, 90, 60, and 30 days before the notice-by date, plus the notice-by date and the renewal date. Preventive maintenance, warranty end, and a contract that does not auto-renew include all-day events 30 and 7 days before the date, plus the date itself. Duespan does not send reminder emails. Keep your own copy of important dates and use Export to back up your data. The "No warranty" section above applies to the app too.
Your use
You may use the calculator and spreadsheet for your own business. Don't enter patient information. Don't misuse or try to disrupt the site.
Changes and law
We may update these terms; the date above shows the latest version. These terms are governed by the laws of the State of Oklahoma.