Free client concentration checker
How much of your income walks out of the door if your biggest client leaves? The working rule behind this checker: once one client passes roughly a third of your income, they stop being a client and become a single point of failure — and past half, they are effectively an employer who can dismiss you without notice. Enter what your five biggest clients pay in a typical month and the checker shows your biggest client's share, the share your top two hold together, and the line that matters most: whether the income left behind still covers your essential month. On the preset numbers, one client pays $2,400 of a $5,000 month — 48.0% — and the remaining $2,600 still covers $2,200 of essentials, by $400. That is a practice to watch, not a cliff. The checker tells you which one yours is.
Your five biggest clients
A typical month, honestly — not your best month, which flatters every share at once. Leave a row at zero if you have fewer than five clients: zero rows are not counted as clients. The costs line is what turns a share into a verdict, and it is the same number the emergency fund calculator builds a fund from.
Your concentration, measured
| Monthly income | $0.00 |
| Clients paying you (rows above zero) | 0 |
| Biggest client pays | $0.00 |
| Biggest client's share | — |
| Top two clients' share | — |
| Income left if your biggest client leaves | $0.00 |
| Your essential costs | $0.00 |
| Left after essential costs | +$0.00 |
Enter your clients' monthly amounts and this line reads the shape of your practice back to you.
Worked example
A freelancer with five clients paying $2,400, $1,200, $800, $400 and $200 in a typical month, and a bare-bones month that costs $2,200 — rent, bills, food, insurance, minimum payments and the tools the work cannot happen without. Enter those numbers above and the checker returns exactly this:
| Monthly income | $5,000.00 |
| Clients paying | 5 |
| Biggest client pays | $2,400.00 |
| Biggest client's share | 48.0% |
| Top two clients' share | 72.0% |
| Income left if the biggest client leaves | $2,600.00 |
| Essential costs | $2,200.00 |
| Left after essential costs | +$400.00 |
| Verdict | Watch it |
Read the shape of it. Nothing here is on fire: five clients, none of them half the practice, and the four smaller ones together still pay the essential month with $400 to spare. The watch is real, though — the biggest client is one reorganisation away from pausing, and 48% sits close enough to half that a year of growth on their side and none on yours crosses the line by drift. Now change one number: make the biggest client $4,000 of a $4,800 month and the same checker turns into a warning — 83.3% from one client, $800 left behind, $1,400 short of essentials. Same trade, near enough the same income, completely different risk. The share is the difference.
How to read the result
- Share of income, not client count. Five clients sounds diversified until one of them pays most of the rent. The risk lives in the proportions, so the checker weighs the money, not the names: a practice of five clients with one at 70% is more exposed than a practice of two clients at 50/50 — and this page will say so, because it reads the amounts, not the headcount.
- The bands are planning heuristics, not laws. Under roughly a third, no single client can sink a month. Between a third and a half, one client is a large slice — a pause hurts, and is worth planning for. Past half, one decision in someone else's business controls the majority of your income. Where exactly your line sits moves with the terms around the client: a retainer with a notice period is a slower risk than the same share paid project to project — the retainers guide covers how that protection is built.
- The costs line decides whether concentration is dangerous or merely notable. A 48% client whose departure still leaves your essentials covered is a watch; the same 48% with the remaining income below your essential month is a cliff, because the gap starts the month they leave, not the month you replace them. That is why this checker asks for your essential costs and prints the left-after-essentials line in dollars, not just the percentage.
- Use a typical month, not a best one. A best month flatters every share at once — the big client looks smaller and the small ones look sturdier than they are. If your income is seasonal, average the last few months per client and enter the averages; the verdict is only as honest as the month you feed it.
And one connection worth making: concentration measured in months of cover is exactly what the emergency fund calculator sizes — its target already lengthens when one client dominates. Measure the shape here; build the cushion there.
And the mirror image: this page prices what a client puts at risk. The client lifetime value calculator prices what the same client is worth — across every project they will ever send you, not just this month's. Read the two together and the anchor client stops being a feeling in either direction: a value, an exposure, and a fund sized between them.
What to do with a concentrated practice
A bad result is information, not an emergency — the client has not left; you have simply seen, early, what it would mean. Work the list in this order:
- Build the fund first. Saving is the only item on this list fully in your control, and it converts a cliff into a slope: months of essential costs in reserve are months in which a lost client is a problem to solve rather than a crisis to survive. The emergency fund calculator sizes it from the same essential month you entered above.
- Grow the small clients; do not fire the big one. The fix for a heavy top line is a heavier base, not a smaller practice. The anchor client is usually your best reference, your steadiest payer and the proof behind your next proposals. The niching guide argues for narrowing on evidence — run its logic in reverse here, and widen the base on the evidence of this page. Diversify the denominator and the share falls on its own.
- Price the risk into the next renewal. A client who is half your income and knows it holds a negotiating card; a client whose rate quietly includes the concentration they create is paying for the risk they represent. The rate negotiation guide covers holding a price with the reasoning shown — and this page is part of that reasoning.
- Set a personal cap, and review it on a schedule. Decide the largest share you are willing to carry — a third is a defensible line — and write it where your planning lives. The year-end checklist's client-list exercise is the natural moment to re-run this checker: the list you write there is the input this page runs on.