Eight free interactive calculators for the recurring math of running a SaaS — pricing tiers, runway, unit economics, processor fees, and AI margins. Live calculations, no signup, no email gate.
Most SaaS calculators on the internet are lead-magnet wrappers. You type two numbers, the tool spits out a glossy chart, and a form asks for your email before showing the “full report.” That is not what a solo founder needs. A solo founder needs to type a number, see the answer, and have a one-sentence interpretation telling them whether the answer is good, bad, or fine. That is what the calculators on this page are. Each one is a live web tool that computes in the browser, requires no signup, and ends with a small color-coded pill telling you what the result actually means in solo-founder context.
The calculator suite is also opinionated about what the right benchmarks are. Most SaaS-metric benchmarks circulating online are scraped from VC-backed companies at Series A and later. Solo founders operate at a different scale and with a different cost structure. The LTV:CAC calculator's interpretation pill knows that at $500 MRR your CAC is probably $0 because you are doing distribution by hand. The churn calculator knows that 5% monthly churn is catastrophic for an enterprise tool but normal for a $9 consumer app. The valuation calculator knows that solo SaaS sells at 2-4x ARR, not the 10-15x that public-company analysts quote. The benchmarks are tuned for indie reality.
The eight tools below cover the four math problems every solo founder runs into more than once a month: pricing, unit economics, runway and exit, and cost. If you bookmark one page on the site, this is a reasonable candidate. The pricing and processor-fee calculators come up before launch. The runway calculator comes up the first time you do a quarterly plan. The LTV:CAC, churn, and payback calculators come up the first time you spend money on ads. The valuation calculator comes up the first time someone reaches out to acquire your product. The AI token calculator comes up the first day you turn on Claude in production. Each of these moments is a real decision, not an exercise.
Every formula on every calculator is shown directly on the page, with the source for each benchmark cited (Stripe's public pricing, Anthropic's public pricing, SaaS Capital's public surveys, MicroAcquire's public listing data, our own SaaS metrics that matter reference). No calculator silently substitutes numbers. No calculator routes you through a paywall. Last reviewed May 2026 with current Stripe, Lemon Squeezy, Paddle, Anthropic, and OpenAI pricing.
Pricing is the highest-leverage decision a solo founder makes and the one most often skipped on instinct. The two calculators in this group answer the two pricing questions that come up before launch: “at this price, how many customers do I need to hit my MRR goal” and “at this price and processor, how much do I keep after fees.” Both are simple math, both are easy to get wrong in your head, and both change the founding decision of what your first three tiers look like.
The pricing calculator is where to start if you have no price yet. Plug in three tier prices and an MRR target and the tool shows the customer count required at each tier, plus the LTV that price implies at a default churn assumption. The honest answer is usually that your $9 tier requires 1,000 customers, which most solo founders cannot reach, and that you should consider whether a $29 or $49 starting tier serves a customer who actually wants what you are building. The processor-fee calculator answers the follow-on question: if you charge $29/month, how much arrives in your bank account after Stripe vs Lemon Squeezy vs Paddle? At the volumes most solo SaaS runs at, the difference between processors is 1-3% of revenue — not life-changing but not nothing.
Unit economics is what determines whether your SaaS is a business or a hobby. Three numbers run it: how much each customer pays you over their lifetime (LTV), how much it costs to acquire them (CAC), and how fast you get that acquisition cost back (payback). The three calculators in this group are the cheapest way to get a real number for each of those without rolling a spreadsheet from scratch.
The LTV:CAC calculator implements the canonical 3:1 ratio with a solo-founder honesty layer: at zero paid acquisition, your CAC is approximately zero, and the 3:1 ratio becomes meaningless. That is fine; the calculator says so. The interpretation pill changes once you start spending on ads and the ratio starts mattering. The churn calculator is the brutal one. It shows months until you have lost half your customers and revenue lost to churn at month 12 — numbers that turn the abstract “5% monthly churn” into “half your business is gone in 13 months,” which is the framing that gets founders to actually fix churn rather than nodding at it on dashboards. The CAC payback calculator answers the survival question: how many months until a new customer pays back what you spent acquiring them. Solo founders bootstrapping cannot afford 14-month payback periods. The pill knows.
Runway is the survival metric for solo founders not yet at default-alive. Valuation is the exit metric for solo founders considering a sale. Both are usually thought about by spreadsheet and usually thought about wrong because the formulas that get quoted in funding-stage SaaS land do not apply at indie scale. The two calculators here translate.
The runway calculator answers three questions at once: how many months of cash do you have, what month do you break even at your current growth rate, and where will MRR land at month 12? That last one is the most useful because it tells you whether the current growth rate is enough to get to default-alive before the cash runs out. If it is not, the answer is to either grow faster or cut costs — usually the latter, in solo land. The valuation calculator gives a realistic estimate of what your SaaS would sell for today, based on ARR, growth rate, net revenue retention, and profitability margin. The output is a range, not a number, because that is how acquirers actually negotiate. The methodology section under the tool shows the multiples MicroAcquire, Acquire.com, and SaaS-broker comps come in at, so the range is grounded in real data rather than a generic 5x ARR formula.
The newest calculator in the suite is the most important one for AI-native SaaS. Token costs decide whether your AI product has a viable gross margin or whether you have built a charity that gives Anthropic and OpenAI free distribution. Every AI SaaS founder needs to do this math before launch, and most do not, which is why the first cohort of AI SaaS startups discovered at $3K MRR that their margin was 18% and that the product unit economics did not work.
The AI token cost calculator handles four model providers (Claude Sonnet, Claude Haiku, GPT-4o, GPT-4o-mini) at three usage profiles (light chatbot, medium retrieval, heavy generation) and computes monthly cost at your DAU and message volume. It surfaces the four cost levers (prompt caching, smaller models for routing, batch API where possible, retrieval limits per query) as toggles so you can see how much each one saves. The margin warning at the bottom is the same one our true cost of running an AI SaaS essay walks through in detail — if your token cost is more than 30% of revenue, you have a real margin problem that needs a structural fix, not a deal with the model provider. If you are building anything AI-native, do this math before you write the first prompt.
If you are pre-launch, work through them in this order. First, the pricing calculator — before you write a landing-page price. Second, the processor-fee calculator at your expected price point to know your take-rate. Third, the AI token cost calculator if your product is AI-native, before you scope the API budget. After launch, the runway calculator becomes the once-a-month sanity check, the churn calculator becomes the early-warning indicator (a single bad month is signal, not noise, at solo scale), and the LTV:CAC and CAC payback calculators come online as soon as you start any paid acquisition channel. The valuation calculator is the one to ignore until someone reaches out to buy your product — obsessing over exit value at $500 MRR is a known time sink, and the answer is “not enough yet” either way.
None of the calculators talks to a server. Numbers stay on your machine, the math runs in your browser, and there is no email gate. If you find a benchmark you disagree with or want a new calculator added to the suite, contact details are at the bottom of every page and the SaaS metrics that matter companion guide is a sensible next stop for context on why each of these numbers is the one to track instead of the dozens that are not.
The stack, prompts, pricing, and mistakes to avoid — for solo founders building with AI.