PERCENTAGE-FEE CALCULATOR
When does Substack’s 10% cost more than a flat monthly plan?
Enter your paid-subscription revenue and the flat monthly price you are considering. We’ll show the direct platform-fee difference and the crossover point.
At $1,000 revenue, 10% costs $100. A $43 flat fee is $57 lower.
The text file includes your inputs, the result, what it leaves out, and when we checked the sources. It is created on this device.
$430/month in paid revenue.
Payment processing, taxes, refunds, discounts, migration work, and the value of platform features.
HOW THE NUMBER IS WORKED OUT
One multiplication, one subtraction, one division
- 01
Revenue-share cost. Monthly paid-subscription revenue multiplied by the revenue-share rate.
- 02
Monthly difference. The revenue-share cost minus the flat monthly price. The result shows the size of the gap and says which fee model is lower.
- 03
Crossover. The flat monthly price divided by the rate. Above that paid revenue, the flat fee costs less; below it, the revenue share costs less. At a 0% rate there is no crossover, because the share never costs anything.
- 04
Nothing else is added. Payment processing, taxes, refunds, and discounts sit outside both figures, so the result compares platform fees only.
WORKED EXAMPLE
The starting inputs, step by step
The form opens with $1,000 of monthly paid revenue, a 10% share, and a $43 flat price. The 10% rate is the creator fee Substack documents on paid subscriptions (source checked September 22, 2026). The $43 is an example flat price, not a quote for a specific plan.
- Revenue share
- $1,000 × 10% = $100 a month.
- Monthly difference
- $100 − $43 = $57 a month lower with the flat fee.
- Crossover
- $43 ÷ 10% = $430 of monthly paid revenue. At exactly $430, both models cost $43.
- A smaller publication
- At $250 of monthly paid revenue, the 10% share is $25, so the revenue share is $18 lower than the $43 flat fee.
A lower fee does not make the whole platform better
Audience discovery, recommendations, community features, and a familiar publishing workflow may be worth paying more for. This calculator only compares the fee models.
Before moving, use the migration calculator to see how long the monthly difference would take to repay the switching work.
Payment processing still applies. Substack documents its fee as charged in addition to payment-processing fees, and paid subscriptions elsewhere still need a payment processor. Leaving processing out of both sides keeps the comparison to platform fees, so the difference is not your full take-home change.
Use an average month. Paid revenue changes as readers join and cancel, and annual subscriptions arrive in one payment. Enter a typical monthly figure. Taxes, refunds, discounts, and currency conversion are not modelled; amounts are in US dollars.
Check the flat plan itself. Confirm the price you enter matches your list size and billing period on the provider’s pricing page, and that the plan supports paid subscriptions and the features you rely on.
YOUR NEXT STEP
Test the crossover against real plans.
The Substack alternatives guide works through the crossover for flat monthly prices, with five checks before you count a lower fee as a saving. If the gap is worth pursuing, the migration calculator shows how long it takes to repay the move, and the platform cost calculator shows checked plan prices at your list size.
PRIMARY SOURCES
Verify the current price before you buy.
- Kit paid-plan documentation ↗Re-check overdue
- beehiiv pricing ↗Re-check overdue
- Substack creator fee documentation ↗Re-check overdue