Every number in a startup has a definition and a rule behind it.
Stack Ledger explains the metrics, funding instruments, budgets, board packages and equity rules a growing software company runs on. Every sourced figure carries a numbered link to the page it came from, and each source shows the day we read it.
One month of recurring revenue, posted line by lineUnits, illustrative
| Line | What it records | Amount |
|---|---|---|
| Opening recurring revenue | What customers already pay each month | 100 |
| New customers | Customers who were not there last period | +18 |
| Expansion | Existing customers who upgrade or add seats | +12 |
| Contraction | Existing customers who downgrade | (4) |
| Churn | Customers who cancel | (9) |
| Closing recurring revenue | 117 |
Net revenue retention on this sheet: (100 + 12 − 4 − 9) ÷ 100 = 99%, because new customers are left out. Our arithmetic on round numbers, not data from any company.
What is on the books
Every published page, with the question it answers.
| Section | Page | The question it answers |
|---|---|---|
| SaaS metrics | Net revenue retention: formula, example, benchmarks | I read "NRR" in an investor update and want to compute it |
| ARR vs MRR: difference, formula and when to use each | MRR is recurring revenue per month and ARR is the annual figure, but ARR has two definitions. Formulas, a worked example, GAAP revenue and how filers define it. | |
| SaaS churn rate: formula, examples and benchmarks | Churn rate is the share of customers or recurring revenue lost in a period: the formulas, a worked example, benchmarks and how public filers define it. | |
| CAC payback period: formula, example and benchmarks | CAC payback period is the months of gross profit a new customer needs to repay their acquisition cost: formula, worked example, benchmarks and filer recipes. | |
| SaaS revenue recognition: ASC 606 steps and examples | How SaaS companies recognize revenue under ASC 606: the five steps, deferred revenue, upgrades, refunds, usage fees, commissions and worked examples. | |
| Fundraising mechanics | How venture rounds work: seed to exit, step by step | I need to know what a funding round actually changes |
| SAFE notes: how they work, convert and what they risk | A SAFE is a contract for shares later, not a loan: how the valuation cap sets ownership, when it converts, how it differs from a note, and the risks. | |
| Convertible notes: how they work, terms and example | How a startup convertible note works: interest, maturity, discount, valuation cap, what happens if the company fails, plus a worked example and SEC-filed terms. | |
| Finance operations | Burn rate and runway: formulas, example and benchmarks | Burn rate is the cash a startup uses each month and runway is how many months it lasts: formulas, a worked example, benchmarks and the going-concern test. |
| Startup annual budget: how to build one, with example | How to build a startup annual budget in six steps: revenue drivers, fixed and variable costs, headcount, cash, a SaaS spend benchmark and a worked example. | |
| Scaling startup finance: five stages, roles and costs | How startup finance scales: five maturity stages, signals it is time to upgrade, controller and CFO roles, G&A benchmarks, CFO pay and the audit horizon. | |
| Boards and reporting | Startup board financial package: what to include | What a startup board financial package contains: three statements, a short KPI set, burn and runway, budget-versus-actual variance and a narrative. |
| Startup board of directors: roles, duties and seats | What a startup board of directors does, the duties its members owe, how many seats a startup board has at seed and Series A, and how a filing shows one grow. | |
| Startup equity | Startup stock options: ISO vs NSO tax, 409A, Rule 701 | I am offering options and need the tax rules straight |
| 409A valuation: what it is, how it works, what it costs | A 409A valuation sets the fair market value of a startup's common stock and the strike price of its options: the rule, the three steps, cost and timing. | |
| 15 pages in 5 sections | ||
15pages in 5 sections, each with a numbered source list
125distinct sources, 55 of them regulators, standards bodies or company filings
October 21, 2026latest check. How pages are checked · What changed