Why software gets funded and services usually do not, and why a low-margin business cannot grow its way out of trouble.
Gross margin is gross profit as a percentage of revenue: (Revenue − COGS) ÷ Revenue.
It answers one question: of every dollar a customer pays you, how much is left after delivering what they bought?
Because gross margin determines what the business can afford to do.
At 80% margin, $100 of revenue leaves $80 to pay for sales, engineering and everything else. At 25%, the same $100 leaves $25 — so you need four times the revenue to fund the same team.
This is why investors treat margin as a structural fact about the business rather than a number to be improved later. It decides whether growth helps you or hurts you.
Two companies, both at $500,000 of revenue.
SaaS company: COGS $100,000 (hosting, payment fees, support). Gross profit $400,000. 80% margin.
Agency: COGS $375,000 (the salaries of the people delivering the work). Gross profit $125,000. 25% margin.
The agency must reach $1.6M of revenue to have the same gross profit the SaaS company has at $500k — and to get there it has to hire proportionally more delivery staff, which keeps the margin at 25%.
Neither is a bad business. But only one of them gets meaningfully better as it grows.
First-time founders often exclude their own or their team's delivery time from COGS because 'we would be paying ourselves anyway'. That makes a services business look like a software business on paper, right up until you try to hire someone to do the delivery and the margin collapses to its real value.
The honest test: if you doubled customers, which costs would automatically double? Those are COGS, whoever currently absorbs them.
Hosting, per-seat third-party APIs, payment processing, direct customer support, and any delivery labour.
If a human must do work for each customer, their time is COGS. This is the step most founders skip and it is the one that matters most.
(Revenue − COGS) ÷ Revenue. Write it down as a percentage, monthly.
Software typically 70–90%. Marketplaces vary hugely by take rate. Hardware and e-commerce 20–50%. Services 20–40%. Being far below your category's norm is a signal, not a detail.
Automating manual delivery, changing pricing, or moving upmarket can all raise margin. If none of them can, that is real information about what kind of company this is.
Whenever pricing, when choosing which customers to serve, and before any fundraise. Margin is one of the first things a serious investor checks.
Do not obsess over it in the first few months when volumes are tiny and every fixed cost distorts the percentage. Get it roughly right, then watch the trend.
Apply this to your own startup in My Full Journey (free account).