No category has more seductive vanity metrics than developer tools. A thousand GitHub stars, a Hacker News front page, a spike of signups — all of it feels like traction, and none of it tells you whether developers actually depend on your tool. A star costs one click and means nothing. Product-market fit is whether the developer is still using you in production three weeks later.
The benchmark is 40%, and for dev tools it's a particularly useful reality check against the applause.
Is the PMF benchmark different for developer tools? No — it's still 40%. It just cuts through the stars-and-signups noise that dev tools accumulate.
Who counts as an engaged user for a dev tool
Your engaged user is a developer who has actually integrated the tool and shipped something with it — it's in their codebase, their pipeline, their workflow. Someone who starred the repo, skimmed the docs, or signed up to try it later hasn't experienced the product. Survey the people who are in production, and your score will tell you something the star count never could.
Bottom-up adoption changes who you ask
Developer tools spread bottom-up: an individual developer adopts you, then the team, then eventually someone buys a plan. That means the person whose product-market fit you care about is the developer using the tool daily, not the engineering manager who approved the bill. As with B2B SaaS, survey the user, not the buyer — but in dev tools the gap between the two is especially wide.
What "very disappointed" looks like for a dev tool
The fit signal in developer tools is unmistakable when you hear it: "I'd hate to go back to doing this manually." The best dev tools remove a specific, recurring pain — boilerplate, debugging, deployment, glue code — and the developers who'd be devastated to lose you are the ones who remember what life was like before. The open-ended answers will name the exact chore you eliminated. That's your positioning and your roadmap.
See where you land against 40%
The free PMF score calculator runs the Sean Ellis survey on your users and shows your score against the benchmark — no signup.
Calculate your PMF score → Built on the Sean Ellis 40% method.How to measure PMF for a developer tool
- Ignore the vanity metrics. Stars, upvotes, and signups aren't fit. Survey developers who've shipped with the tool.
- Survey the user, not the buyer. The daily-driver developer is your respondent, even if someone else pays.
- Listen for the eliminated chore. "I'd hate to do this by hand again" is the dependency you're looking for.
- Track it as you grow. Bottom-up tools can plateau quietly; a tracked score catches stalling fit before revenue does.
Developers are a tough, honest audience — they'll happily star a repo and never use it again. The PMF survey is how you find out who's just clapping and who genuinely can't work without you.
Measure your fit, find your ICP, track the trend
PMFtracker runs the Sean Ellis survey on your engaged users, scores you against the 40% benchmark, surfaces your ICP from the open-ended answers, and tracks the trend over time.
Start measuring free → Set up in 5 minutes · No credit card required
