SellerToolsOnline

Free · No signup · Runs in your browser

Free online tools and calculators
for sellers

Calculate Amazon FBA profit, eBay fees, Etsy fees, shipping cost, margins, markup, and product pricing before you list on any marketplace.

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100% Free
No hidden fees, no freemium
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Private
Calculated in your browser only
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Embeddable
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Free online tools for ecommerce sellers

Use these free seller calculators to estimate marketplace fees, profit margin, shipping cost, markup, break-even point, and product pricing. Every tool is free to use — no sign-up, no fees, no limits.

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Amazon FBA Calculator
Calculate Amazon US FBA profit, margin, ROI, and seller fees before you source or reprice inventory.
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FBA Fee Calculator
Enter your product dimensions and weight — estimate your FBA fulfillment fee and size tier
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FBA Storage Calculator
Estimate monthly FBA storage cost from inventory volume and storage rate
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FBA vs FBM Calculator
Compare FBA and FBM profit per order before choosing a fulfillment method
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Referral Fee Calculator
Estimate Amazon referral fees by sale price and category before pricing a product
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Profit Margin Calculator
Calculate gross profit margin, net margin, and markup — and understand the difference between them
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Break-Even Calculator
Estimate the units and revenue needed to break even — before you source or launch
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ROAS Calculator
Find the ROAS you need before ads turn a product unprofitable
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Price Calculator
Calculate the selling price you need from cost, target margin, or markup
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Bulk Pricing
Calculate volume discount prices, order totals, customer savings, and profit before you send a bulk quote
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Proforma Invoice
Create a professional preliminary invoice for a buyer, calculate the total, and download it as a PDF
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Commercial Invoice
Prepare a customs-ready international shipment invoice and download a professional PDF
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Product Pricing Calculator
Enter your costs and target profit margin — estimate the price you should charge
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Markup Calculator
Calculate markup percentage, convert markup to margin, and find the right selling price from cost
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Markup to Margin
Convert markup percentage into profit margin before you set a selling price
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Landed Cost Calculator
Add every cost from factory to your warehouse door — know your true cost per unit before you place the order
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Shipping Calculator
Estimate domestic package shipping costs by weight, dimensions, and zone. Compare planning estimates for USPS, UPS, and FedEx before pricing an online order.
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International Shipping
Estimate international parcel shipping cost before pricing cross-border orders
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Dimensional Weight Calculator
Calculate DIM weight and billable weight from package dimensions before pricing shipping, FBA fees, or oversized parcels.
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Shopify Calculator
Estimate Shopify order profit after product cost, shipping, fees, and ads
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Poshmark Calculator
Estimate Poshmark seller fees, net profit, and take-home payout before listing
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eBay Fee Calculator
Enter your eBay sale price and costs — estimate fees and real take-home profit
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Etsy Fee Calculator
Enter your Etsy sale price and costs — see every Etsy fee and your real take-home profit
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Etsy Digital Profit
Estimate Etsy digital download profit after listing fees, transaction fees, payment fees, and ads
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Seller Guides

Practical pricing, fee, and profit guides for online sellers.

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Guide

How to Price Products for Online Selling

Learn how to price products for online selling using landed cost, markup, profit margin, marketplace fees, shipping cost, and break-even volume.

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Guide

eBay Fees Guide

eBay fees guide for sellers. Learn how final value fees, shipping charged, item cost, and examples affect net profit before using the calculator.

Read guide →

Built by an Amazon seller, not a content farm

I've been selling on Amazon North America since 2019. Every calculator on this site reflects real fees I deal with daily — FBA size tiers, referral percentages, inbound shipping estimates. I built these tools because I couldn't find a free one that got the math right.

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