Building real things, in public
Notes from DEMHA FUTURE — how we build apps fast with AI, and what we learn.
Earnings Disclaimer Generator — free online
Make a clear, FTC-compliant earnings disclaimer for your course or coaching, free and online — right in your browser, nothing uploaded.
eBay Fee Calculator — free online
Work out eBay fees, your net profit and margin for any sale, free and online, right in your browser with nothing uploaded.
EBITDA Calculator — free online tool
Work out EBITDA and your EBITDA margin from net income and add-backs, free and online, right in your browser with nothing uploaded.
Effective Annual Rate Calculator — free online
Turn a nominal APR into the real effective annual rate (APY) for any compounding, free and online, right in your browser with nothing uploaded.
Effective Tax Rate Calculator — free online
Find your effective tax rate, take-home pay and take-home % from your income and tax — free online, right in your browser, nothing uploaded.
Eisenhower Matrix — free online planner
Sort your to-dos by urgent and important and get a clear plan, free and online, right in your browser with nothing uploaded.
Email A/B Test Calculator — online, free
Free email A/B test calculator. Enter sends and replies, opens or clicks for each subject line and see if the winner is real, right in your browser.
Email Disclaimer Generator — free online
Make a confidentiality or legal footer for your email signature, free and online, right in your browser with nothing uploaded.
Email Formatting Cleaner — free online tool
Paste messy or forwarded email text and get clean, paste-ready plain text — free and online, right in your browser, nothing uploaded.
Email Inbox Preview — free online tool
See how your email looks in the inbox before you send it, free and online, right in your browser with nothing uploaded.
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