StartupLenz

Cost calculators for niche indie founders, free forever

Side Project

No-Code

Finance

This is the first product I've ever shipped to real users. I'm not a serial founder with multiple SaaS launches behind me. I’m just a guy whose wife built a cool spreadsheet that I thought might help other people. My wife was getting into a new hobby, slimes, and wanted to know what it would cost to create her own brand. So before investing she built a spreadsheet to model that process. Nothing about that in itself is really unusual. I’ve done the same thing myself no less than 20 times. But when I looked at what she'd built, I thought she’d captured something that was actually pretty cool and ultimately useful. And the best part, at least to me, was she didn’t even realize what she had. The data she captured was deep, and her presentation of it (compared to other options for niche business models) was fantastic. It made me wonder, "Would this same pattern work for any other DIY business someone is considering?" Could we model a food truck the same way? A cleaning service? A subscription box? Turns out yes, once you commit to one model per vertical instead of pretending they're all the same kind of business, the whole thing clicks. That's how StartupLenz ended up at ten verticals (slime, food truck, candle, subscription box, print-on-demand, digital products, cleaning service, handmade, reseller, house flipping) with more on the way. The thing that makes it different: the defaults aren't hardcoded. They live in a database and update as marketplace fees shift, material prices fluctuate, and channel economics change. When Etsy bumps a fee or TikTok Shop's average sell-through moves, the calculators reflect it. When inflation hits your input costs, our models adjust with the markets. Most cost calculators get less accurate every month after they ship. I built the living pathways so this one doesn't. A few other things I tried to do right: Channel-aware revenue (model the Etsy / TikTok / own-site split, not an averaged blob) An insight function, not just charts (the model engine reads your numbers and tells you the most relevant thing to fix first) Free, no email gate, no "upgrade to see your full report" nonsense I'd love feedback on: Anyone who’s ever started a business in one of our 10 verticals. If you've operated in those spaces, are the defaults reasonable? What vertical you wish was modeled next. Service businesses (lawncare, beauty, mobile auto-detail) are coming in the next batch. Try it: www.startuplenz.com. Pick a vertical, slide some sliders, tell me what's wrong.