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E-commerce Seller Tools

31 tools

All 31 calculators

FBA

Amazon FBA Fee Calculator

Estimate Amazon referral and FBA fulfilment fees, then see net profit per unit and your real margin.

Calculate →SHOPIFY

Shopify Profit Calculator

Per-order profit after COGS, shipping, payment processing and your Shopify plan costs.

Calculate →ETSY

Etsy Fee Calculator

Listing, transaction, payment and offsite-ad fees on one screen, with profit after cost.

Calculate →PRICING

Product Pricing Calculator

Work out the price you need from a target margin or markup, plus a margin ladder for comparison.

Calculate →BREAK-EVEN

Break-Even Calculator

Units and revenue needed to cover fixed costs at a given price and variable cost.

Calculate →ROI

ROI Calculator for Ecommerce

Return on investment from revenue and cost, with profit and multiple shown together.

Calculate →PROFIT

Net Profit Calculator

Revenue down to net profit through COGS, operating expenses and tax, with both margins.

Calculate →MARGIN

Gross Margin Calculator

Gross margin and markup from revenue and COGS, side by side so the difference is obvious.

Calculate →MARKUP

Markup Calculator

Selling price from cost and markup percentage, with the resulting margin shown for contrast.

Calculate →DISCOUNT

Discount Percentage Calculator

Final price and savings from a discount percentage, plus the implied discount between two prices.

Calculate →SHIPPING

Shipping Cost Calculator

Estimate parcel shipping from weight and zone, with fuel surcharge broken out.

Calculate →DIM

Dimensional Weight Calculator

Billable weight from box dimensions and actual weight, across all three common divisors.

Calculate →INVENTORY

Inventory Turnover Calculator

Turnover ratio and days inventory outstanding from COGS and average inventory.

Calculate →REORDER

Reorder Point Calculator

The stock level that triggers a reorder, based on daily sales, lead time and safety stock.

Calculate →LEAD TIME

Lead Time Calculator

Total replenishment lead time from ordering, production, shipping and buffer days.

Calculate →PACKAGING

Package Size Estimator

Recommended box dimensions from product size plus cushioning, with volume and DIM weight.

Calculate →FREIGHT

Freight Class Calculator

Density-based NMFC freight class estimate from weight and carton dimensions.

Calculate →ROAS

ROAS Calculator

Return on ad spend with the break-even ROAS that matches your margin.

Calculate →CPC

CPC Bid Calculator

Maximum cost per click from your target CPA and conversion rate.

Calculate →CVR

Conversion Rate Calculator

Conversion rate from orders and sessions, with the sessions-per-order view.

Calculate →CAC

Customer Acquisition Cost Calculator

Blended CAC from total acquisition spend and new customers acquired.

Calculate →LTV

Customer Lifetime Value Calculator

LTV from average order value, purchase frequency, lifespan and gross margin — plus LTV:CAC.

Calculate →EMAIL

Email Open Rate Calculator

Open rate, click-through and click-to-open from a campaign's sends, opens and clicks.

Calculate →SOCIAL

Social Media Engagement Calculator

Engagement rate from interactions and reach, benchmarked against typical ranges.

Calculate →TAX

Sales Tax Calculator

US sales tax from a base amount, state rate and local rate, with the combined rate shown.

Calculate →VAT

VAT Calculator

Add VAT to a net amount or extract it from a gross figure, in one tool.

Calculate →GST

GST Calculator

Goods and services tax for Australia, Canada, India, Singapore and New Zealand.

Calculate →DUTY

Import Duty Calculator

Duty on the CIF value plus total landed cost for an import shipment.

Calculate →CUSTOMS

Customs Clearance Calculator

Full clearance cost: duty, import VAT/GST and broker fees on one landed-cost line.

Calculate →1099

1099 Tax Estimator

Self-employment tax plus federal income tax on 1099 income, with quarterly payment amounts.

Calculate →SE TAX

Self-Employment Tax Calculator

Just the 15.3% Social Security and Medicare tax on self-employed net profit.

Calculate →

What you can calculate here

Thirty-one calculators for the numbers behind an online store: marketplace fees and net profit, pricing and break-even, shipping and inventory, ad efficiency (ROAS, CAC, LTV) and the sales-tax and duty questions that decide whether a product is actually profitable.

How to use these tools

Each calculator asks for plain numbers you already have — price, cost, weight, hours, rate — and returns the figure that decides the decision: margin, break-even volume, take-home pay, runway. Every page states its formula and its assumptions, so you can check the arithmetic instead of trusting a black box.

Frequently Asked Questions

Are the marketplace fee figures exact?

They are close estimates based on published 2025 rate cards. Amazon and Etsy change fees by category and size tier, so confirm in Seller Central or your Etsy shop manager before pricing a large run.

Do these tools connect to my store?

No — everything is manual entry and runs locally. That is deliberate: no OAuth, no data leaving your browser.

Which tool should a new seller start with?

The Amazon FBA calculator or Shopify profit calculator, then the break-even calculator to find your minimum viable price.