The Real Cost Method
This is the name we give to how every calculator on The Lean Stack arrives at its numbers. No calculator on this site uses a hidden formula - here's exactly how each one works, what it assumes, and where the pricing data comes from.
Why this page exists
A calculator that shows you a number without showing its work is asking for blind trust. We'd rather you could check our math - or catch us when a vendor's pricing has changed and we haven't updated it yet. Every result on every calculator links back to this page, and every formula below is the actual code running behind the tool, not a marketing simplification of it.
Core principles behind every calculator
- Pricing is checked against each vendor's public pricing page at the time a calculator is built or updated, never estimated or guessed. When a plan's pricing structure doesn't fit neatly into a simple model - HubSpot's onboarding fees, ActiveCampaign's pricing-by-contacts rather than by seat - we say so explicitly next to the number rather than smoothing it over.
- We tell you when a link is an affiliate link, right next to the link itself, not just in a footer disclosure. Where no affiliate relationship exists, the calculator says that too, rather than silently omitting a CTA. See our full affiliate disclosure.
- Every calculator's inputs are shareable. The "Share this result" button on each tool copies a link that encodes your exact inputs in the URL - opening that link reproduces your result for anyone, with no account or re-entry required.
- Prices change. We do our best to keep this page and each calculator current, but every result includes a reminder to confirm current pricing directly with the provider before making a purchasing decision. Found something out of date? let us know and we'll fix it.
Funnel Cost Calculator
Used on the funnel cost calculator.
We add up the monthly cost you enter across seven categories - website/hosting, landing page builder, email software, CRM, automation, course platform, and other tools - for your current monthly total, then multiply by 12 for the annual total.
The "consolidated" comparison figure uses a fixed reference point of $27/month - the approximate cost of Systeme.io's Startup plan, which bundles the equivalent functionality into one subscription. Potential annual savings is your current annual total minus the consolidated annual cost ($27 × 12), floored at zero so the tool never shows a negative "savings."
Email Marketing Cost Calculator
Used on the email marketing cost calculator.
Your current annual cost is simply your entered monthly cost × 12. The estimated alternative cost looks up your contact count against a fixed set of tiers modeled on Systeme.io's pricing (2,000 contacts free, 5,000 for $27/mo, 15,000 for $47/mo, above that $97/mo), then annualizes that tier's monthly price the same way. Savings is the difference between the two annual figures.
Affiliate Income Calculator
Used on the affiliate income calculator.
This one is a straight funnel-math chain, with no vendor pricing data involved:
- Estimated clicks = monthly traffic × click-through rate
- Estimated conversions = estimated clicks × conversion rate
- Estimated monthly income = estimated conversions × average commission
- Estimated annual income = estimated monthly income × 12
These are illustrative, not predictive - real affiliate income depends heavily on traffic quality and offer fit in ways a four-input calculator can't capture. We say this directly on the tool itself, not just here.
Online Business Cost Calculator
Used on the online business cost calculator.
The simplest tool on the site: we add your entered monthly cost across seven categories (hosting, domain, email marketing, funnel builder, course platform, scheduling, other tools) for a monthly total, then multiply by 12 for the annual total. No comparison figure, no assumptions beyond the numbers you enter.
CRM Cost Calculator
Used on the CRM cost calculator.
This is the most involved calculation on the site, comparing HubSpot, Pipedrive, Zoho CRM, ActiveCampaign, and Freshsales. For each CRM:
- Your selected team size is matched against that vendor's tier brackets (1-5, 6-15, 16-40, 41+ users) to find the applicable plan and its per-seat price.
- Total monthly cost = per-seat price × team size - except ActiveCampaign, which prices by contact-list size rather than seats, so its tiers are shown as a flat monthly cost regardless of your team size input. This is the single most common way a generic "per-seat" CRM calculator misrepresents ActiveCampaign, and we specifically built around it rather than forcing it into the same formula as the other four.
- Feature match = the share of your selected features (automation, email marketing, advanced reporting, integrations/API, sales pipeline, priority support) that vendor's plan actually includes.
- Ranking: results are sorted first by whether the per-seat (or flat) price fits your selected budget ceiling, then by feature match percentage, then by total price - so the top result is always a genuine fit for your stated budget, not just the cheapest option regardless of what you said you needed.
Two vendors - Zoho and Freshsales - are shown with pricing but no "Try it" button, because neither currently has a public affiliate program we could join. We'd rather show you the honest comparison and lose the commission than quietly drop a competitively priced option from the results.
Corrections and feedback
If you spot a stale price, a broken calculation, or a vendor whose plans have changed since we last checked, tell us - these tools are only as useful as the numbers behind them are accurate.