SaaS Idea Validation Checklist.

A SaaS idea validation checklist is a structured set of tests an indie founder runs before writing a single line of code, to find out whether the idea is worth building. The FoundStep checklist is 8 stages and 43 individual checks covering gut check, problem validation, market and demand signals, competitive teardown, solution and economics, pre-build market test, qualitative customer contact, and the final go/no-go build decision. Four of the stages have explicit "KILL IF" thresholds so you know exactly when to stop.

Roughly 2 to 4 weeks of focused part-time effort end to end. Stage 1 takes an hour. Stages 2–5 are 2 to 5 days each. Stage 6 (the paid market test) is 1 to 2 weeks of running ads. Stage 7 (customer interviews) is optional. The whole point of the kill criteria is to compress this further: most weak ideas die in Stage 1 or Stage 2 within the first 3 days, which means you spend 2–4 weeks of validation instead of 6 months building the wrong product.

Because most ideas are bad and the cost of building the wrong thing for 6 months is far higher than the cost of killing it in week 2. If you only chase success criteria, every signal looks like a "yes" and confirmation bias does the rest. The FoundStep checklist puts a written kill threshold on every meaningful stage so you have a pre-committed exit point. When you hit the threshold, you don't debate it. You stop, write down what you learned, and pick a different idea.

Yes, completely free. No signup, no email gate, no upsell. Tick items in the browser, your progress saves to localStorage automatically. Download the PDF, Markdown, or Excel version with one click. We make money on FoundStep subscriptions, the project management tool. The checklist exists to attract indie SaaS founders who care about shipping discipline.

In your browser's localStorage, scoped to this domain. Nothing is sent to a server. If you tick 12 items today and close the tab, the next time you open the page on the same browser those 12 items will still be ticked. If you switch browsers or devices, the progress does not transfer (because it never left your machine). Use the "Reset progress" button at any time to wipe and start over.

Different workflows. Markdown is best if you live in Notion, Obsidian, Linear, or your code editor: paste it once, get auto-converted checkboxes and headings. PDF is best for printing, sharing with a co-founder, or attaching to a board update. Excel is best if you want a sortable view of every item, want to add custom columns (status, owner, notes), or use formulas to track completion.

Two options. Option 1 — copy-paste: open the .md file, copy everything below the "How to use" section, paste into a new Notion page. Notion auto-converts the `- [ ]` checkboxes, `##` headings, and `>` quote blocks. Option 2 — file import: in Notion go to Settings → Import → Markdown & CSV and upload the .md file directly. Option 1 gives you cleaner formatting, Option 2 preserves the document structure as a single page.

Most competitor checklists are 5-step frameworks with a single PDF download and 2 to 6 FAQ entries. The FoundStep checklist is 8 stages, 43 individual checks, and 4 explicit kill thresholds, and you can run it interactively in the browser with auto-saved progress, or take it offline in Markdown / PDF / Excel. It is also opinionated: it will tell you to kill the idea, not just to "consider next steps".

Yes, with caveats. Stages 1–4 (gut check, problem validation, market signals, competitive teardown) apply unchanged to any new business. Stage 5 (economics) needs different unit-economics assumptions for ecommerce (margin × repeat purchase) or marketplaces (take rate × transaction volume × liquidity), but the structure still works. Stage 6 (paid landing page test) works identically. The FoundStep tool is opinionated for indie SaaS because that's the audience that fits the kill-criteria style best.

After. Interviews are Stage 7 in this checklist, and they are deliberately marked optional. A pre-build paid landing page test (Stage 6) measures revealed preference: people clicked, gave you a card, gave you an email. Interviews measure stated preference, which is famously unreliable when the question is "would you pay for this?". Use interviews to enrich understanding of users who already showed signal, not to gather fake demand.

In Stage 4, that is almost always a red flag, not a green flag. "No competitors" usually means one of three things: the problem isn't painful enough for anyone to monetise, you're using the wrong search terms (look for indirect competitors and substitutes), or the market is so technically hard that incumbents have tried and failed. The healthy version is "no competitor at this exact price tier or for this exact segment", not "no one has ever done this". Always include "do nothing" and "spreadsheet" as substitutes in your competitive map.

Benchmarks for Stage 6 after 500 to 1,000 targeted paid visitors: under 1% means kill (people don't care). 1 to 3% means re-test with a sharper hook. 3 to 7% is promising. Above 7% is a strong signal. Crucially, weight by CTA strength: paid pre-orders > deposits > book-a-call > email waitlist. Five paid pre-orders is more validating than 500 emails. Email-only waitlists should be discounted heavily because the cost of joining is near zero and most signups will never convert.

Kill if Stages 1, 2, or 3 fail (no real users, no real complaints, no real market). Pivot if Stages 4 or 5 fail (gap exists but positioning is wrong, or unit economics need a different price point or segment). Pivot if Stage 6 fails (CTA below 1%) but qualitative interviews surface a sharper adjacent pain. Build only if Stages 1–5 pass kill criteria AND Stage 6 hits real conversion AND you can articulate the one-paragraph "why now / why you" answer in Stage 8.

Stages 1–5 cost $0. They are research and writing. Stage 6 (the paid landing page test) is $300 to $500 in ad spend to drive 500 to 1,000 targeted visitors, plus $0 to $30/mo for a landing page builder if you're not coding it yourself. Stage 7 conversations are free. Total cost to validate any SaaS idea before writing code: roughly $300 to $600. Compare this to 6 months of opportunity cost building the wrong thing.

Painkillers cost users real money, real time, real reputation, or real opportunity right now if not solved. Vitamins are nice-to-have improvements people would adopt if it were free and effortless, but won't pay for. The clearest test is to look at current workarounds (Stage 2): if users are duct-taping spreadsheets, paying contractors, or burning weekends, the problem is a painkiller. If everyone shrugs and says "I'd use it I guess", it's a vitamin.

Stage 2 specifically benefits from AI-assisted research: paste 100 Reddit/G2/Capterra complaints into a model, ask for clusters by frequency and exact-phrase extraction. Stage 3 (TAM estimation) is good for AI calculation. Stage 5 includes a "red team" item where you ask AI for 20 reasons your idea fails and address the top 5. AI does not replace any stage. It accelerates the parts that are tedious.

You move from validation to building. The classic next step is locking your MVP scope (the smallest version that delivers core value, defined in Stage 5) and committing to a ship deadline. FoundStep is built precisely for this: it enforces a complete project lifecycle so you can't silently expand scope after validating, can't skip the build phase, and can't leave the project in "almost done" forever. Validate with this checklist, ship with FoundStep.

FoundStep, a project management platform purpose-built for indie developers and solo SaaS founders. The 8-stage structure is informed by Paul Graham's "default alive" framework, David Sacks on capital efficiency, the Y Combinator Startup School curriculum, Indie Hackers community patterns, and direct conversations with bootstrapped SaaS founders. The kill-criteria emphasis is the FoundStep house view: discipline beats optimism on every meaningful timescale.