RCRotoCurve
Seller toolkit

eBay Seller Toolkit

A practical hub for profit, fees, shipping, offers, and break-even listing decisions. Use it to check the math before you source, list, ship, discount, or scale.

RotoCurvePrimary calculator

Open a related RotoCurve calculator for this seller workflow.

RotoCurveBreak-even math

Open a related RotoCurve calculator for this seller workflow.

RotoCurveShipping math

Open a related RotoCurve calculator for this seller workflow.

RotoCurveMargin math

Open a related RotoCurve calculator for this seller workflow.

RotoCurveROI math

Open a related RotoCurve calculator for this seller workflow.

Fast checklist

  • Calculate net profit after marketplace and payment fees.
  • Include shipping, supplies, returns, and ad cost before calling an item profitable.
  • Use break-even price before accepting offers or running discounts.
  • Recheck assumptions when fee schedules or carrier rates change.

Quality and usage notes

This page is intended to help users make clearer planning decisions with transparent assumptions. Results are estimates and should be checked against official sources when money, taxes, shipping, or marketplace rules are involved.

How to use this page well

Use this page as a planning aid, not a final quote or official rule. Replace defaults with your own numbers, compare more than one scenario, and check any important fee, tax, carrier, or marketplace policy against the official source before acting.