Each one answers a single question from a file you already have. No account, no email, no trial. Your file is read in your browser and never sent anywhere — the pages are blocked from making network requests at all.
Drop in your orders export. Finds the days each SKU went unusually quiet against its own weekday pattern, estimates what that likely cost, and says plainly which SKUs it cannot judge.
Drop in your Klaviyo profile export. Shows what is really in your contact count, split into what is provably unreachable and what needs your judgement. Anyone who has ever bought from you is excluded before anything else runs.
The forward-looking one. The formula written out in full, why safety stock scales with the square root of lead time rather than linearly, a worked example, and the three cases where the formula hands you a confidently wrong answer. Do it by hand from the page, or use the calculator on it.
The free two answer a question about the past, which a static page can do completely. Reorder Copilot answers a question about money you are about to spend, and that took real work to get right — mainly the work of making it refuse to answer where the data can't support it. It is a one-time price rather than a subscription because there is no server behind it, so charging you monthly would be charging for nothing.
Both tools would be easy to make more impressive. The stockout calculator could put a number on every slow-moving SKU instead of excluding them; List Diet could mark "never opened" as safe to delete and show you a much larger saving.
Both would be wrong, and the cost of being wrong lands on you — a purchase order for stock you did not need, or a suppression list that quietly removes customers who were buying but never opening. So where the data genuinely cannot answer a question, these say so instead of guessing, and the totals come out lower than a less careful tool would show you.
If you find a number that looks wrong, please tell me what your data looked like. I would rather fix it than have someone act on it.