PROFITABLE GROWTH SIMULATOR

How much can you spend on advertising before profit disappears?

Most growth plans get locked to a single efficiency target. The reality: once margin, variable costs, and fixed costs are on the table, there is a range of profitable ways to scale. This tool is built to answer the hard questions:

• How do we spend more and make more?
• At what point does profit start to diminish?
• When do we push harder, and when do we pull back?

It runs on your real economics: margin, processing fees, shipping, returns, and cancellations. Set your numbers and the profitable path shows itself. Let's jump in.

MER (Marketing Efficiency Ratio) measures how much of your revenue is spent on advertising.

Spend $15 on ads to generate $100 in revenue? Your MER is 15%. It's a useful benchmark, but a 15% MER can be highly profitable for one business and unprofitable for another. The difference comes down to margins, variable costs, and scale.

The map below plots every daily ad-spend × revenue combination and the MER it produces. Green is efficient, red is heavy. Tap or hover any cell to see how the same MER shows up across many spend/revenue pairs.

// The interactive MER map is best on desktop. Scroll down to run your numbers.

Start with your gross margin, then layer in variable costs (processing fees, outbound shipping, returns, cancelled orders) and fixed costs (OpEx & wages). Build your current plan as Scenario A — edit daily or monthly, spend or revenue, and everything stays in sync.

Variable costs move with your sales — every order pays its own processing, shipping, and returns. These percentages change as your business grows: rates get negotiated down, return and cancellation rates shift with your product mix and customers.

Fixed costs and OpEx don't scale with each order — they're the monthly overhead your margin has to clear. As revenue grows they shrink as a share of sales, which is where scale pays off. Revisit them as you hire and grow.

Add Scenario B above with a higher spend, and this section answers the three questions that follow: how much extra revenue the new spend needs to break even, whether profit actually goes up, and what revenue it would take to hold your current profit. All of it uses your effective margin — after variable costs and cancellations.

Set the monthly contribution margin you want (revenue × effective margin − ad spend) and see the paths that get there. Same goal, different mixes of efficiency, spend, and revenue. Uses the effective margin set above — gross margin minus variable costs, after cancellations. Drag the slider or type any number.

Every row hits the same contribution margin. Lower efficiency (higher MER) is viable, it just requires more revenue and more spend to get there.

Start with the monthly net profit you want after fixed costs & OpEx. Same idea, many paths to the same bottom line. Uses the effective margin, Fixed Costs, and OpEx set above. Drag the slider or type any number.

Every row nets the same profit after all costs. Higher-MER paths simply need more revenue and spend to clear the same bottom line.

Your answer is in the read on your plan at the top, and in your Distance to Breakeven on each scenario. Positive distance means room to scale before efficiency becomes the limit. Negative means pull back, improve efficiency, or attack variable costs — shipping, returns, and cancellations. Switch planning modes to reframe the read for revenue, profit, or scaling.

Blended MER counts every revenue dollar. aMER (acquisition MER) counts only what you spend to win new customers, the truer read on growth. Set your new-customer share and a target aMER. This uses Scenario A's spend and revenue.

// Doesn't model diminishing returns, channel saturation, or cash-flow timing. Pair with incrementality analysis.