For now you can use the following tools completely free of charge:
1) FBA Calculator - a tool to calculate the net and margin for an Amazon product based on ASIN. FBA Calculator is also available in the IO Scout web app.
Read more about the FBA Calculator here.
Try it for free here: https://ioscout.io/fba
2) Sales Estimator - a tool to estimate the number of monthly sales in a specific category based on the product’s sales rank (BSR). Sales estimator can be used as a BSR Estimator, which allows you to calculate BSR needed to achieve your sales projections. Sales Estimation is also available in IO Scout web app.
Read more about the Sales Estimator here.
Try it for free here: https://ioscout.io/sales-estimator
Good luck with your researches!