Fake-door & smoke tests
In one sentence
Test demand before building by offering something that doesn't exist yet and measuring who tries to get it.
The simple version
Put up a landing page, button or pre-order for your idea. If people click, sign up or pay, demand is real. If not, you've saved months. Always be honest afterwards ('coming soon — want early access?').
Why it matters
It turns opinions into behaviour, which is much more reliable.
How to do it
- 1Write a clear one-line promise.
- 2Build a simple landing page or in-app button.
- 3Drive a little traffic (ads, posts, emails).
- 4Measure clicks, sign-ups or pre-orders.
- 5Decide your 'yes' threshold before you start.
Real-world example
Dropbox's demo video drew a flood of sign-ups for a product that wasn't widely available yet — strong evidence to keep building.
What the books say
Test value risk early — fake doors and landing pages measure real interest cheaply.
Common mistakes
- Misleading people without a follow-up.
- Judging on tiny traffic.
- Not deciding success criteria upfront.
Questions people ask
Is it ethical?
Yes, if you're transparent once someone clicks and don't take money you can't deliver on.
References
- [1]
- [2]
More books on this in the library
$100M Offers: How To Make Offers So Good People Feel Stupid Saying No
Teaches startups to create 'Grand Slam Offers' that maximize perceived value and minimize buyer risk, driving higher conversion rates in customer acquisition. Vs Traction Channels, it focuses on offer optimization to make channel spend more effective, with use cases in SaaS, agencies, and e-commerce boosting LTV 3x+. Critical for go-to-market product-market fit validation.
The Sales Acceleration Formula: Using Data, Technology, and Inbound Selling to go from $0 to $100 Million
HubSpot's Chief Revenue Officer Mark Roberge shares the data-driven playbook that took HubSpot from zero to $100 million. Essential for B2B SaaS founders building scalable sales organizations.
Amazon Storefront – Startup Books Collection
An Amazon store collection page that aggregates multiple startup-related books in one place. While the specific titles are not visible in the provided content, the link points to a curated Amazon product listing that can be used to browse and purchase various must-read books for startup founders (e.g., titles similar to “Zero to One,” “The Lean Startup,” etc.).
Unknown Startup Book (Amazon Listing B0BXBJ3R5R)
An Amazon book product with ASIN B0BXBJ3R5R. The provided data is a tracking/redirect URL without a visible title or description, but it clearly refers to a book listing on Amazon. Due to truncated content, the exact book name and details are not identifiable from the supplied text alone. It appears in a pricing context and is likely a business or startup-related book, but this cannot be confirmed from the given snippet.
Hacking Growth: How Today's Fastest-Growing Companies Drive Breakout Success
Sean Ellis and Morgan Brown outline growth hacking tactics for founders, including cross-functional teams testing acquisition, activation, retention levers. Key metrics like viral coefficient and North Star Metric drive scaling teams via rapid experiments. Vs Blitzscaling, it focuses on data-driven efficiency over pure speed.
Do More Faster: Techstars Lessons to Accelerate Your Startup
Brad Feld compiles accelerator tactics for founders to accelerate growth through rapid iteration, team building, and customer validation. Key metrics include weekly progress velocity and milestone achievement for scaling early teams. Vs. Blitzscaling, it focuses on structured acceleration for pre-scale startups.
Learn next
Minimum Viable Product (MVP)
The smallest version of your product that lets you learn whether you're on the right track.
Customer discovery
Go and talk to real potential customers to check that the problem you want to solve actually exists.
Product discovery & the four risks
Before building, check four risks: will they buy it, can they use it, can we build it, and does it work for the business?