Building real things, in public
Notes from DEMHA FUTURE — how we build apps fast with AI, and what we learn.
ROAS Calculator — free online tool
Work out ROAS, ACoS and break-even ROAS from your ad revenue and spend, free and online, right in your browser with nothing uploaded.
Robots Meta Tag Generator — free online
Pick the directives you need and get the correct robots meta tag to paste into your HTML, right in your browser, nothing uploaded.
Robots.txt Generator — free online tool
Make a valid robots.txt online for free, right in your browser. Pick a preset or set rules per bot. Nothing is uploaded.
Robots.txt Tester — free online tool
Check if a URL is allowed or blocked by your robots.txt — free and online, right in your browser with nothing uploaded.
ROI Calculator — free online tool
Work out return on investment, net profit and annualized ROI for free online, right in your browser with nothing uploaded.
Roman Numeral Converter — free online
Turn numbers into Roman numerals and back in a second, free and online, right in your browser with nothing uploaded.
Rotate & Flip Image — free online tool
Rotate or flip a photo and download it, free and online — right in your browser, with nothing uploaded.
Rotate PDF online — free, no install
Rotate PDF pages 90° or 180° online and download — free, right in your browser, nothing uploaded.
RSA Ad Preview — free online tool
See how your Google Responsive Search Ad will look before you launch it — free and online, right in your browser, nothing uploaded.
Rule of 72 Calculator — free online
See how many years it takes to double your money, free and right in your browser, with nothing uploaded anywhere.
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