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LEXUNCreate your KeyRun a decision free
For fractional CFOs

One repeatable decision process, across every client.

You rebuild the same spreadsheet for every client’s consequential call, and the reasoning leaves with you at the end of the engagement. LEXUN gives each decision the same discipline: classified evidence, 5,000 scenarios, the downside and the breakpoint, a board-ready record, and a review date on which the forecast is graded. The record stays with the client.

The decisions it runs, client after client

How long is cash runway under downside conditions?

Not the plan case: the tenth percentile, the stress scenario and the month the cash turns.

business runway model
What happens if a major customer leaves?

Revenue stepped down by the customer’s share, costs held, the twelve-month test re-run on the same seed for a like-for-like comparison.

business runway model · compared alternatives
Can they take on this debt?

Repayments added to monthly costs; the breakpoint tells you the revenue growth the facility needs to be safe.

business runway model
Can they increase owner drawings?

Drawings as a cost line; the probability band before and after, and what the increase does to the worst tenth of paths.

business runway model
What is the safe hiring point?

The cost level that breaks the runway, named on the result; the hire goes in when the plan clears it with room.

sensitivity and breakpoints
How much working capital is needed?

The cash figure at which the band reaches the probability the board will accept, solved by re-running the same model.

explore: reach a target probability

One client decision, worked

If revenue falls 20% below plan, does the business keep positive cash for the next 12 months?

The first case a fractional CFO runs is the downside. Revenue 20% below plan — £24,000 instead of £30,000 — against £27,000 of monthly costs and £60,000 in the bank, with no growth assumed. Illustrative figures; the shipped engine’s arithmetic, at a fixed seed.

Probability the business keeps positive cash to month 12

50–60%

genuinely uncertain — a range, never a point, because the inputs are uncertain and the model says so.

Downside
Under the stress case (Revenue −25%, growth −2pt, volatility +5pt) survival falls to 14%. That is the number to plan around, not the headline.
Breakpoint
The median path reaches the horizon at or above -0.4%/month revenue growth; you stated 0%.
Biggest lever
Monthly costs moves the answer most; a stressed month there swings survival by about 59 points.
Cash runway
In the worst tenth of paths the cash lasts 7 months; in the best tenth, 12+.
The test reality applies
On the review date, was the business cash balance greater than £0 (no insolvency event, no emergency rescue funding required)?

The figures · cash £60,000 · revenue £24,000 a month · costs £27,000 a month · growth 0% a month · volatility 15% · horizon 12 months. Each is labelled a fact or an assumption before the engine runs.

5,000 paths · runway@1.0.2 · seed 564 · receipt rw_ee3fad2c_234 · reproduce this exact result · run it on your own figures

What changes for you

The process, client after client

1 · Frame

One question with a checkable outcome and a date it resolves on.

LIVE
2 · Evidence

Every figure a fact or an assumption, with its source, date and owner.

LIVE
3 · Run

5,000 seeded paths: the band, the downside, the breakpoint, the lever.

LIVE
4 · Challenge

The case against, the assumptions it leans on, and what would change the answer.

LIVE
5 · Record

Recommendation, approval and success criterion frozen and sealed under one hash.

LIVE PILOT
6 · Review

Reminders for the review date; the outcome scored against the frozen criterion.

LIVE

Live means on one person’s device today, free. Reviews and approvals across a team are facilitated by LEXUN during the founding pilot; the self-serve shared workspace is planned for Release 2 and labelled so on every page that mentions it.

Why the board can trust it

Reproducible

Same figures, same seed, same answer, on any machine. Every result carries its receipt; anyone can check it.

Private by architecture

The engine runs in the browser. Client figures are not uploaded; the optional Copilot is the one exception and says so before you use it.

Test-gated, not accuracy-claimed

862 automated checks prove the software behaves as written. No accuracy percentage is published until ten outcomes have resolved in a domain.

Scored in public

LEXUN’s own forecasts are frozen and graded on the public register, misses included.

The detail, and the limits, are in the Trust Centre and the Accuracy Centre.

How it is priced

Free
£0

The full engine, unlimited runs, no card and no account. Saving needs a free LEXUN Key.

Pro
£9 a month

or £79 a year: every decision kept, exports and the PDF record. Checkout opens when Stripe is switched on.

Organisation seat
£49 a seat a month

or £490 a year, ex VAT: Pro for every seat plus the board report and the audit-trail export.

Founding pilot
£1,500

30 days, one real decision, with a person. Credited against the first four annual seats.

All of it on one page, with every line labelled: pricing.

Questions fractional CFOs ask

Does the record stay with the client when I leave?

Yes. Records are saved on the device under a LEXUN Key and exported as a PDF and a sealed package that anyone can verify without LEXUN. Hand the export over and the reasoning outlives the engagement.

Can I run the same decision for two clients without mixing them?

Each decision is its own record with its own figures, seed and receipt; the demonstration data and your own decisions never mix. Shared workspaces that separate clients by organisation are planned for Release 2 and are labelled planned until they ship.

How is a paid seat different from the free engine?

The maths is identical. A seat buys the record: every decision kept, exports and the PDF, the board-report generator and the audit-trail export. Nothing marked planned is sold as if it existed; the entitlement matrix says exactly what is in a seat today.

What if the question is outside the three models?

LEXUN refuses it rather than approximating. Debt facilities, drawings, customer loss and hiring are all runway questions today; pricing strategy, valuation and investment returns are not modelled and the engine says so.