Four free tools. Three need no signup.
The fourth one, the inventory planning app, asks for an account. The other three do not. Each runs on the same thinking our planning runs on: lead time as a path, stock as coverage, decisions with dates on them. Use them on your own numbers, keep whatever they produce, and if the outputs worry you, that is exactly what the Fit Call is for.
Pick by the question in front of you.
Supply chain map builder
Drag your suppliers, freight legs, warehouses and channels onto a canvas, connect them, and the critical path computes as you build. Exports as a PNG you can put in front of a team or a forwarder. The fastest way to see your real lead time as a path instead of a guess.
Supply chain health score
A short diagnostic on how your planning actually runs: visibility, stockout exposure, cash discipline, process maturity. It will also tell you if you are too small for a managed layer, which is a real answer this site gives on purpose.
Stockout cost calculator
Four sliders on your last dark stretch: margin gone while dark, the recovery tail you bought back, and the date the preventing decision was actually due. Your inputs, your arithmetic, nothing asserted about your business.
Inventory planning app
Upload the reports you already download from Seller Central and it computes sales velocity, days of supply and the date to order by, per product and per marketplace. This is the only one of the four that needs an account, email and password, because it holds your uploaded reports between sessions.
All four are free because they are the parts of the method that work without us: seeing the path, scoring the process, pricing the failure, computing the numbers. The part that needs people is keeping it all true every week, and deciding what to do when it is not.
If you are weighing vendors, not tools.
The compare section maps the whole landscape by the question each shelf answers: planning software, management systems, seller suites, profit analytics, agencies, enterprise platforms, and where the weekly decision actually lives.
Want to validate a result against your operation?
Bring the map, the score, or the calculation to the fit call. The working session uses your operating data, not the tool result alone.