If you are still deciding whether an idea deserves your next year, you don't need an operating system for a business you haven't started. IdeaProof sells to exactly that moment. You describe the idea, spend some credits, and get a validation score and reports. There's no subscription.
Nautis solves a later problem. It assumes you have tasks, investors, invoices or customers to keep track of, and its AI gets useful only as those records build up. Read this page as a question of timing. IdeaProof's pages are rendered by script, so in October 2026 we read its prices and FAQ from the script file its pricing page loads, and used a page reader for the rest.
What does validating an idea involve?
Validation means finding evidence that real people will pay for what you plan to make. A tool can help with the desk research, such as market size, competitors and risks. It can't stand in for talking to buyers, and IdeaProof's own page says its scores are decision support and not a prediction. Our guide on customer interviews covers the part software can't do.
IdeaProof's first step is Idea Validation, with a score and a GO or NO-GO signal. Its later steps add Market Analysis with TAM, SAM and SOM sizing plus a competitor map and risk flags, then a Business Plan, Brand Strategy, Visual Identity and a Marketing Suite of ads and copy. Nautis approaches this differently. Its Pitch Deck Analyzer has an Idea Validation tab that tests market, demand signals and risks, but it runs on a deck you've already made. We also offer a lighter free idea validator on this site, and it needs no subscription.
How IdeaProof's credits add up
One useful thing IdeaProof publishes is the credit cost of each step, so you can work out what you'll spend before you begin. As of October 2026, prices include VAT for EU customers, there's no subscription, and the page says credits never expire. Signing up gives you 40 credits with no card, which covers one validation.
| Step | Credits | Running total |
|---|---|---|
| Idea Validation | 40 | 40 |
| Market Analysis | 50 | 90 |
| Business Plan | 100 | 190 |
| Brand Strategy | 50 | 240 |
| Visual Identity | 150 | 390 |
| Marketing Suite | 250 | 640 |
So one idea taken through all six steps costs 640 credits, which helps make sense of the packs below. Its FAQ explains the spread: a Validation is one focused report, while a Business Plan or Marketing Suite runs multi-stage research and generation across many sections.
Packs against plans
| Option | Price | What you get |
|---|---|---|
| IdeaProof starting credits | €0 | 40 credits, or one validation |
| IdeaProof Starter | €19.99 once | 150 credits, covering validation, market and brand for 1 idea |
| IdeaProof Builder | €49.99 once | 1,400 credits, about 2 ideas through all six steps |
| IdeaProof Founder | €99.99 once | 4,500 credits, about 7 ideas through all six steps |
| Nautis Launch | $49 a month | Workspace with 5 team members and 1,000 AI credits a month |
| Nautis Voyage | $99 a month | Adds the cap table, with 10 team members and 2,000 AI credits a month |
| Nautis Fleet | $129 a month | 25 team members and 2,600 AI credits a month |
Every plan includes PDF exports and email support. Its FAQ says all sales are final and it doesn't offer refunds, and suggests trying the 40 starting credits first. Note, too, that a Nautis credit and an IdeaProof credit aren't the same unit, so comparing the counts directly tells you nothing.
Nautis vs IdeaProof by founder stage
| Your stage | IdeaProof | Nautis |
|---|---|---|
| A few ideas, no commitment | Built for this. Cheap and quick to try | Too early |
| One idea, talking to customers | Market and competitor reports help frame interviews | Too early, unless you need tasks and notes |
| Deck drafted, thinking of raising | Business plan and brand outputs | Deck analysis, readiness score, investor list |
| Company formed, first customers | Not a listed focus | Leads CRM, invoices, runway, task boards |
| Raising a round | Not a listed focus | Fundraising CRM, data rooms, voice coach, cap table on Voyage and Fleet |
| Team of 5 to 25 | Not a listed focus | Team records, chat, meetings, Chief of Staff briefing |
Read from the top, the handover is easy to spot. IdeaProof's six steps finish at about the point where Nautis starts.
An idea weekend, costed out
Suppose you have three ideas and one free weekend. Spend the first morning writing down who would buy each one and how you'd reach them. Run each through a validator. On IdeaProof, Validation and Market Analysis at 90 credits each come to 270 credits for three ideas, which is more than Starter holds and well within the Builder pack at €49.99. Discard the weakest, then book five customer calls for the idea you like most.
None of that requires Nautis. Nor does the following week, when you'll use a notes app and a calendar. Nautis's value appears some months later, when you have a co-founder, a pilot customer, a founders' agreement to sort out and a growing list of investors. By then, you'd lose little by having spent €50 on a validation, and you might have saved months.
How to read an idea score
IdeaProof's page describes its match rate as an internal metric and says to treat scores as decision support. That's a sensible way to read any idea score, from any vendor: as a prompt for questions. The same goes for our own tools. A low Nautis deck score isn't a verdict on your company, and a GO signal from any tool doesn't mean anyone will pay. Use the score to decide what to ask customers next.
What each is better at
IdeaProof
- Speed and a low cost to reach a first read on an idea, with credits you can spend later.
- One flow from validation through to brand and marketing assets, which Nautis doesn't aim to produce.
- Paying once, which fits someone who isn't sure they will carry on.
- Comparing several ideas side by side, which the packs are sized for.
Nautis
- Running the company afterwards, across fundraising, finance, sales and the team.
- Keeping a SWOT analysis, GTM plans and business plans tied to the same records you use every day.
- An AI Chief of Staff that reads those records each morning and asks before acting.
- It isn't cheap for someone just exploring: $49 a month with no $0 tier, a 14-day trial, and a young product that launched publicly in July 2026.
Where to begin today
- Start with IdeaProof, or our free validator, if you have only an idea. Then go and speak to buyers.
- Start with Nautis if you already have customers, a team or a raise to manage. Our pages for first-time founders and solo founders describe that point in more detail.
- Don't buy both at once. There's no real overlap in time, so buy the one you need now. Keep the validation reports and upload them to a data room later if an investor asks how you tested the market.
FAQ
Should I use Nautis vs IdeaProof to validate a startup idea?
Use IdeaProof or a similar validator first, since it's built for this and costs little. Nautis only offers idea validation inside its deck analyzer, which assumes you already have a deck. Either way, talk to potential customers, because no score replaces that.
How much does IdeaProof cost?
As of October 2026, its one-time packs are Starter at €19.99, Builder at €49.99 and Founder at €99.99, including VAT for EU customers, and there is no subscription. New accounts get 40 credits with no card, which covers one validation.
Do IdeaProof credits expire?
Its pricing page says credits never expire. It's a useful feature if you test ideas now and then rather than continuously. Its FAQ also says all sales are final, so try the 40 starting credits before buying a larger pack.
Disclosure: We make Nautis, so we have a stake in this comparison. It's based on published information, not a scored hands-on test. Spotted something out of date? Tell us and we will correct it.
Sources
- IdeaProof: pricing page, read from its script file and a page reader (checked Oct 31, 2026)
- IdeaProof: homepage, read through a page reader (checked Oct 31, 2026)