UK E-Commerce Calculators
Here is the thing about selling online in the UK: that product with a "60% margin" on your spreadsheet? Once you add up Amazon referral fees, FBA storage, advertising, returns, VAT, and payment processing, you might actually be making 8%. We have seen it happen over and over. Someone sources a product, lists it on Amazon, the sales roll in, and three months later they realise they have been losing money on every unit. The maths is not hard -- but nobody does it properly before they commit to 500 units sitting in a warehouse.
In 2025, UK e-commerce fees are not getting any cheaper. Amazon referral fees run 8-15% depending on category, FBA fulfilment starts at £1.63 per unit and climbs fast for anything bigger than a paperback, and if you hit the VAT threshold (£90k turnover), that is another 20% to factor in. TikTok Shop is cheaper on fees but the audience is different. Shopify gives you better margins but you are paying for every click yourself. These tools let you plug in your actual product costs and see the real profit per unit across every platform -- side by side, with nothing hidden. Compare Amazon FBA fees by product size, model your TikTok Shop margins, or build a proper launch budget before you spend a penny on stock.
All E-Commerce Tools (4 live)
E-Commerce Profit Calculator
Calculate true profit per product after fees, shipping, returns, VAT, and advertising costs.
Amazon FBA Fee Calculator
Calculate Amazon FBA fees including storage, fulfilment, referral, and long-term storage charges.
TikTok vs Amazon vs Shopify Margin
Compare profit margins across TikTok Shop, Amazon, and Shopify for your products side by side.
Product Launch Checklist Generator
Generate a step-by-step product launch checklist customised for your platform and product type.
Frequently Asked Questions
How do I calculate profit margins for e-commerce products?
True e-commerce profit requires accounting for all costs beyond the product price: platform fees (Amazon referral fees are 8-15%, eBay 10-13%, Shopify transaction fees 2-3%), fulfilment costs (pick, pack, and ship or FBA fees), shipping to the customer, returns and refunds (typically 5-15% of sales depending on category), advertising spend (often 15-30% of revenue for new products), VAT (20% on UK sales if VAT registered), and payment processing fees (1.5-3%). A product with a 60% gross margin can easily have a net margin below 10% after all costs.
How much do Amazon FBA fees cost in the UK?
Amazon FBA fees in the UK include a referral fee (8-15% depending on category), a fulfilment fee (from £1.63 for small light items to £6+ for large items), monthly storage fees (£0.68/cubic foot January-September, £1.03 October-December), and long-term storage fees for items stored over 365 days (£4.60/cubic foot or £0.10/unit, whichever is greater). For a typical small product priced at £20, expect total Amazon fees of around £6-£8 per unit. Always run exact fee calculations before sourcing products.
Which is more profitable: Amazon, Shopify, or TikTok Shop?
Each platform has different economics. Amazon offers massive built-in traffic but charges higher fees (30-40% of revenue including FBA and advertising) and you compete directly with other sellers. Shopify gives you higher margins (only payment processing fees of 2-3%) but you must drive your own traffic, which can cost 20-40% of revenue in advertising. TikTok Shop has lower fees (5% + payment processing) and strong organic reach for viral products, but the audience skews younger and conversion rates can be lower. Most successful sellers use multiple channels.
Do I need to register for VAT if I sell online in the UK?
You must register for VAT if your taxable turnover exceeds £90,000 in any 12-month rolling period, or if you expect it to exceed £90,000 in the next 30 days alone. Amazon sellers should note that FBA sales to EU customers may require separate VAT registrations in EU countries. Voluntary VAT registration can benefit B2B sellers (customers can reclaim VAT) and allows you to reclaim VAT on business purchases. The Flat Rate Scheme (typically 7.5-16.5% depending on business type) can simplify VAT accounting for small businesses.
How do I launch a product on Amazon UK?
A successful Amazon UK product launch typically involves: product research and validation (use tools like Helium 10 or Jungle Scout), sourcing from suppliers (Alibaba, UK wholesalers, or private label manufacturers), creating a compelling listing with keyword-optimised title, bullet points, and A+ content, professional photography (budget £200-£500), initial inventory (typically 200-500 units), PPC advertising to drive initial sales and reviews, and ongoing optimisation. Budget £2,000-£5,000 for a first product launch excluding inventory costs.
What are the best strategies for reducing e-commerce returns?
Returns are a major cost for e-commerce businesses, averaging 10-15% of online sales in the UK. To reduce returns: provide detailed and accurate product descriptions with measurements, use high-quality photos and videos showing the product from multiple angles, include size guides and comparison tools (especially for clothing), set clear delivery expectations, use robust packaging to prevent damage, collect and analyse return reasons to identify recurring issues, and consider offering virtual try-on or AR features. Many sellers find that investing in better product pages reduces return rates by 20-40%.