The quick ratio: the one number that tells you whether growth is real
A founder puts two quarters side by side. Both added $180K of net new MRR. Same growth, the slide implies. But in the first quarter the company booked $220K of new and expansion and lost $40K to churn and contraction. In the second it booked $480K and lost $300K. The net line is identical. The business underneath it is not.
The number that separates them is the quick ratio, and an investor will reconstruct it from your transaction file whether or not you put it on a slide.
What the ratio actually measures
The SaaS quick ratio is gross MRR added divided by gross MRR lost over the same period. New plus expansion on top. Churned plus contracted on the bottom. It ignores the net line entirely, which is the point. A ratio of 4 means four dollars of recurring revenue arrive for every dollar that leaks out.
Run the two quarters above through it. The first: 220 over 40, a quick ratio of 5.5. The second: 480 over 300, a quick ratio of 1.6. Both grew $180K. One is compounding efficiently. The other is running a fast acquisition engine bolted to a leaking tank, and the day acquisition slows, the leak is all that's left.
Net new MRR could not have told you that. It is a difference of two large flows, and a difference hides the size of both.
Why investors anchor on it
The quick ratio survives the things that distort most growth metrics. It doesn't care about your starting base, so a $2M company and a $40M company can be compared on the same axis. It doesn't care about your absolute burn, so it separates the quality of growth from the cost of it. And because it's built from gross flows, it's hard to dress up without leaving a mark in the data.
The rough reading most underwriters carry: above 4 is healthy, growth is clearly outpacing decay. Between 2 and 4 is workable but worth a question about where the churn is coming from. Below 1 means the base is shrinking faster than sales can refill it, and no amount of net new framing will hide a quick ratio under 1 for two quarters running.
These are anchors, not laws. An early-stage company with twelve customers can post a quick ratio of 8 one quarter and 1.5 the next on the strength of a single logo. The number is most useful once there's enough volume that one account can't swing it, which is exactly the point at which founders stop watching it.
The three ways it gets flattered
A quick ratio that looks too clean usually has one of three things underneath it.
The first is the window. Measure it over a month and a single large expansion can lift the ratio to double digits; measure the same business over a trailing year and it settles to its real shape. When the figure you're shown is a single good month rather than a trailing-twelve average, the choice of window is doing the work.
The second is reactivation counted as new. A customer who churned in March and returns in August is not new revenue. Booked into the numerator as new MRR, they inflate the top of the ratio while the original churn already sits in a prior period's denominator. The same dollar improves the number twice.
The third is contraction quietly left out. Downgrades are the most flattering line to drop, because they reduce the denominator without anyone deleting a customer. A quick ratio built on logo churn alone, ignoring the customers who stayed but cut their spend, can read a full point higher than the revenue-weighted version of the same quarter.
What a healthy number looks like over time
A single quick ratio is a snapshot. The trend is the diagnosis. A company holding 4 while it scales is the strong case: decay is growing in line with the base, and acquisition is comfortably ahead of it. A company drifting from 6 down toward 2 over four quarters is telling you the denominator is catching up, even if net new still looks fine, because the leak compounds while the founder is watching the top line.
That drift is the early warning the burn multiple confirms a year later. By the time inefficient growth shows up as cash spent per dollar of net new ARR, the quick ratio has usually been sliding for several quarters. It moves first because it sees the gross flows directly, before they net against each other on the way to the P&L.
What this means for the founder
The quick ratio is not a metric you publish to look good. It's a metric you compute to know whether the growth you're about to raise on is the kind that compounds or the kind that has to be re-bought every quarter. The honest version, trailing twelve months, revenue-weighted, reactivations kept out of new, is the one an investor will build from your data anyway.
Levian computes it from your transaction file the way an underwriter would: gross flows separated, the window held steady, expansion and contraction split out so the denominator is whole. You see the same number the room will see, and the trend underneath it, before anyone else gets to draw the line.