Every fee. Every connection. Every alternative. One question decides your tier.

How many platforms do you sell on? Every paid tier gets the full platform. You choose the scale.

Start with a free Margin Check.

One product. One platform. No account required. Enter your product details and the platform computes every fee that applies — from the published rate cards, sourced and linked. What comes back is the Platform Fee Margin: what the platform passes through to you before your own costs. The named exclusions show you exactly what the full analysis would add.

Run a free Margin Check →

Launching September 2026. See what the analysis looks like →

What it costs. What it answers.

Starter — one platform, full depth.
$29/month
$24/month, billed annually
1 platform · 10 products
What this answers
  • What am I actually keeping on every sale — not the two fees I've been checking, but the full stack?
  • Where did my money go — which fees, which line items, which rate card drove each number?
  • How much does it cost to get paid — every step from platform payout to my bank account?
  • Which of these costs can I change — and what's the trade-off if I do?
  • What happens to every connected cost when I change one input?
  • Is anything changing on this platform that affects my costs?
Most sellers sell on more than one platform.
Growth — see costs across platforms.
$79/month
$66/month, billed annually
3 platforms · 25 products
What this answers
  • Everything in Starter — across three platforms instead of one.
  • Would I make more on a different platform — with the comparison that accounts for what's actually included?
  • What if I change fulfilment method, switch platforms, adjust my pricing — modelled before I commit?
  • Which of my products are most profitable — and which ones aren't, once the full cost stack is applied?
Portfolio — model growth before you spend.
$199/month
$166/month, billed annually
6 platforms · 75 products
What this answers
  • Everything in Growth — across six platforms, seventy-five products.
  • What should I do first — which change, which product, which platform has the highest margin impact?
  • Do the numbers work for a new product or a new marketplace — computed from published rates before I order inventory?
  • How does my portfolio look month over month — and which driver caused each margin movement?

Enterprise

For agencies, multi-brand operators, and high-SKU sellers. Unlimited platforms. Unlimited products. API access. Multi-brand organisation structure. Custom reporting. Dedicated support.

Talk to us about Enterprise →

A platform = a distinct marketplace. Amazon US and Amazon UK are two platforms. Every tier gets the full platform across all cost zones — fees computed, payment alternatives mapped, your costs cascaded.

Not selling yet? See what it would cost before you commit.

$9.99 — one-time

Enter a product you're considering — category, weight, dimensions, target price — and the platform computes the full cost stack on one or two platforms. What the real margin looks like before you've ordered inventory.

This isn't a step toward a subscription. It's a reality check before you commit capital.

Get early access — One-Off

Evaluating a product before you commit capital? Be first in line.

Why a subscription?

Because the analysis your portfolio needs today is wrong by next quarter. Rate cards update. New programmes launch. Your product mix evolves. A one-time calculation is a snapshot of a moving target.

Amazon updated 247 FBA rate cells in January 2026. Most sellers found out three months later when their margins showed it. FineMargins monitors 1,236 source URLs. When a rate card changes, your portfolio re-analyses automatically. You see the impact on the day it hits — not in the quarterly review.

FineMargins re-analyses every month, alerts you when something moves, and shows you exactly what changed and what it costs. The intelligence compounds.

The first month, you enter your products. Every month after, the platform runs the full analysis automatically. Rate card changes, new programme eligibility, fee structure updates — reconciled in minutes, not the hours it takes to check manually. After setup, you open it and the work is done.

Founding member rates locked for life.

Know a seller who's flying blind?

Share your referral link. They get their first month free. You get a month's credit for every seller who subscribes.

Run an e-commerce channel, course, or agency? Apply for the partner programme →

Every fee. Every connection. Every alternative. Computed for your product.

Launching September 2026. Early access subscribers get first access and founding member pricing.

See the full fee breakdown on one product → · What the platform finds across a real business →

See how the platform works, step by step → How it works →