The idea check
Before you spend money on a logo, a website or stock, answer one question: how many customers do you need for this to pay you? It takes ten minutes, and it's the most important ten minutes you'll spend on the idea.
1. Write down four numbers
Guess if you have to. A rough number you can check beats a blank you can't.
- Price: what one customer pays you for one sale.
- Cost per sale: what it costs you to deliver that one sale (materials, shipping, payment fees).
- Monthly bills: what you pay every month no matter how much you sell (software, ads, rent).
- Income goal: what you want to take home each month.
2. Do the sum
Then divide by 30 to get customers per day. "85 a month" sounds abstract. "Three a day, every day" tells you what the job actually is.
3. Ask the reality question
Can you reach enough people to get that many buyers? Most people who see an offer don't buy. If roughly 1 in 50 do (2%, a rough planning guess, not a promise), 85 customers means about 4,250 people need to see your offer every month.
If you have no idea how you'd get 4,250 people to see it, you've found your real problem early, and cheaply. That's the point of the test.
4. If the numbers don't work, change the business, not the maths
- Raise the price. At $79 instead of $49, the same example needs 49 customers, not 85.
- Cut the cost per sale. Cheaper supplier, digital delivery, fewer freebies.
- Sell something bigger or repeated. A bundle, a subscription, a service on top.
Don't fix bad numbers by assuming more customers. That's the one change that costs nothing on paper and everything in real life.
Check your understanding
You sell at $30, each sale costs $10, bills are $200 a month and you want $1,800. How many customers a month?
Your numbers say you need 40 sales a day and you're one person. What's the best first move?