PM Interview Prep, Calibrated

Know what to practice next,
not just what question to answer.

PrepOS is an adaptive PM interview coach. Calibrate your target level, practice the highest-impact questions first, and track your readiness — all in your browser.

Start practicing Learn AI PM
Reviewed questions
250
Tracked concepts
18
Target tracks
6
Account required
None
How it works

From cold start to interview-ready in three loops.

PrepOS is not a question dump. It picks the next rep, adjusts how much support to give, and tells you exactly what to fix before the retry.

01

Calibrate

Tell PrepOS your target level, interview date, weekly hours, and weakest area. The plan re-tunes the moment any of those change.

02

Practice

An adaptive queue surfaces the highest-impact next rep. Coach mode builds skills; Interview mode pressure-tests them.

03

Improve

A transparent six-axis scorecard names what worked, what to fix next, and the specific concept to revisit before the retry.

Why PrepOS

An interview coach with a memory and a method.

Most prep tools hand you questions. PrepOS hands you the right next question, then tells you whether your answer is at the target bar.

Six target tracks

APM, PM, Senior, Staff, AI PM, and PM-T — each with its own readiness bar and depth expectations.

Adaptive queue

Every rep updates concept confidence so the queue keeps closing the gaps that matter most.

Source-aware question bank

Every prompt carries a reviewer, source type, and citation. No fabricated company claims.

Transparent feedback

Six axes, no black box.

Every answer is scored on structure, user insight, metrics, trade-offs, communication, and target-level depth — with a named strength and the single fastest improvement.

Try the scorecard
By a PM, for PMs

Built by an aspiring PM. For the PMs ready to be next.

PrepOS started as my own interview lab — built across multiple PM loops when generic prep guides and free question dumps stopped earning their keep. Same question bank, rubric, and adaptive queue I still run before every onsite.

Principle 01

Honest by default

MVP1 ships with a transparent keyword-and-structure rubric. LLM scoring is on the roadmap and will always be opt-in. No black-box numbers.

Principle 02

Source-aware questions

Every prompt names its reviewer and source type. No fabricated company claims, no scraped content from sources that disallow it.

Principle 03

Local-first by design

Your answers, scores, and progress live in your browser. No account, no per-user tracking, no cookies. Aggregate page-view analytics only — used to understand demand, never to identify you.

FAQ

Straight answers about how PrepOS works.

Is PrepOS free?

Yes. PrepOS is free to use and runs in your browser. No account required.

How is PrepOS different from generic PM interview practice tools?

Most tools are flat question dumps. PrepOS is adaptive — it tells you which rep moves your readiness next, calibrated to APM, PM, Senior, Staff, AI PM, or PM-T target levels. The rubric is open and visible, not a black-box score.

Which PM interview rounds does PrepOS cover?

Six round types: product sense, execution, AI product judgment, behavioral, strategy, and technical collaboration. Each round is mapped to specific concepts so you can train weakest areas instead of grinding generic question banks.

Does my data leave the browser?

No. Your answers, scores, and progress live in your browser. PrepOS does not collect or transmit your answers — only aggregate page-view analytics.

Practice the rep that moves your readiness — not just any question.

Start practicing