How the three liquidity ratios work
Every liquidity ratio divides some slice of current assets by current liabilities — the bills due within twelve months. What changes is how skeptical the numerator is. The current ratio counts everything, inventory included. The quick ratio — the acid test — throws inventory out, on the grounds that stock must besold before it can pay anyone, and a forced sale rarely fetches book value. The cash ratio goes one step further and drops receivables too, since money customers owe is not money in the bank until it is collected. Line the three up and you can see exactly where a company’s liquidity actually lives: in cash, in collections, or in a warehouse.
The formulas
Current ratio = current assets ÷ current liabilities
Quick ratio = (cash + securities + receivables) ÷ current liabilities
Cash ratio = (cash + securities) ÷ current liabilities
Net working capital = current assets − current liabilities
All three ratios share the same denominator; each drops a slower-to-liquidate asset class from the numerator. Net working capital restates the current ratio as a dollar amount rather than a multiple. The conventional readings — current ratio below 1 strained, 1.2–2 typical, above 3 possibly idle capital; quick ratio at or above 1 comfortable — are rules of thumb, and heavily industry-dependent.
Worked example
Take a company with $50,000 in cash, $30,000 in marketable securities, $120,000 of receivables, $150,000 of inventory, $10,000 of other current assets, and $200,000 of current liabilities. Build the three ratios from strictest to loosest:
| Step | Amount |
|---|---|
| Cash & equivalents + marketable securities$50,000 + $30,000 — money that can pay a bill this week | $80,000 |
| = Cash ratio$80,000 ÷ $200,000 current liabilities — the strictest test | 0.40 |
| + Accounts receivablealready earned, not yet collected — the wedge between cash and quick | $120,000 |
| = Quick (acid-test) ratio$200,000 ÷ $200,000 — inventory deliberately excluded | 1.00 |
| + Inventory + other current assets$150,000 + $10,000 — counts as current assets, but must be sold first | $160,000 |
| = Current ratio$360,000 total current assets ÷ $200,000 | 1.80 |
| Net working capital$360,000 − $200,000 — the same test stated in dollars | $160,000 |
Computed with this calculator's default inputs — open the tool above and you'll see the same numbers, then swap in figures from any balance sheet.
Inventory, receivables, and the industry problem
The gaps between the three ratios are as informative as their levels. In the example above, inventory alone separates a current ratio of 1.80 from a quick ratio of 1.00 — most of this company’s apparent cushion has to be sold before it can pay anything. Receivables separate the quick ratio from a cash ratio of 0.40 — earned money that still has to be collected. And the benchmarks themselves travel badly across industries: a grocery chain that turns its shelves every two weeks and collects cash at the register can run a current ratio below 1 happily, paying suppliers out of sales that happen faster than invoices come due, while a heavy-equipment maker with slow stock and 90-day receivables needs a far larger cushion. Standard corporate finance texts — OpenStax’s Principles of Finance, and classics like Ross, Westerfield, and Jordan — make the same point: liquidity ratios are a first screen, read against peers and trend, not a verdict.
Speed is the missing dimension, so pair these snapshots with the turnover measures: thecash conversion cycle calculatorshows how many days cash spends tied up between paying suppliers and collecting from customers, theinventory turnover calculatormeasures how fast the wedge between current and quick actually moves, and thereceivables turnover calculatordoes the same for the wedge between quick and cash.
Frequently asked questions
What is the quick ratio?
The quick ratio — also called the acid-test ratio — measures whether a company could pay its current liabilities using only its most liquid assets: cash, marketable securities, and accounts receivable. It deliberately excludes inventory, because inventory must find a buyer before it can pay a bill, and a company forced to liquidate stock quickly rarely gets full value for it. The formula is (cash + marketable securities + receivables) ÷ current liabilities. A result of 1.0 means liquid assets exactly cover the liabilities due within the year.
What is the difference between the current ratio and the quick ratio?
Both divide by current liabilities; the difference is the numerator. The current ratio counts every current asset — including inventory and prepaid expenses — while the quick ratio strips those out and keeps only cash, securities, and receivables. Inventory is the wedge between them: an inventory-heavy retailer can post a comfortable current ratio and a weak quick ratio at the same time. Comparing the two tells you how much of a company’s apparent liquidity depends on selling stock rather than assets that are already cash or nearly cash.
What is a good quick ratio?
The conventional rule of thumb is that a quick ratio of 1.0 or higher is comfortable: liquid assets fully cover current liabilities without touching inventory. But the benchmark is honest only with context. Businesses that collect cash at the register and turn inventory fast — grocers, restaurants, many retailers — routinely run quick ratios well below 1 without distress, while a manufacturer waiting months for receivables may want a cushion above 1. Compare against industry peers and the company’s own trend rather than treating 1.0 as a pass/fail line.
What is the cash ratio, and when does it matter?
The cash ratio is the strictest of the three tests: (cash + marketable securities) ÷ current liabilities. It ignores receivables as well as inventory, asking whether the company could pay everything due this year from money it holds right now. Most healthy firms run well below 1 — keeping enough idle cash to retire every current liability at once is usually wasteful. The ratio matters most in stress scenarios: a credit crunch, customers suddenly paying late, or a lender assessing worst-case coverage where nothing can be collected or sold in time.
Why can a healthy company have a low current ratio?
Because the ratio is a snapshot, and speed matters as much as size. A grocery chain sells its inventory in days or weeks — often collecting cash from shoppers before its own supplier invoices come due — so its current assets can sit below its current liabilities indefinitely while bills are always paid on time. Suppliers are effectively financing the business. That is why analysts read liquidity ratios alongside turnover measures like the cash conversion cycle: a low ratio with fast turns can be safer than a high ratio built on slow-moving stock.
Sources
- OpenStax, Principles of Finance — free textbook covering financial-statement and liquidity analysis
- OpenStax, Principles of Accounting, Volume 1: Financial Accounting — the balance-sheet classifications behind these ratios
The official figures this page quotes are drawn from the primary sources above — check them (or a qualified professional) before relying on a result.
Disclaimer: This calculator is foreducation and illustration only. Liquidity ratios are point-in-time snapshots from one balance sheet — they say nothing about cash-flow timing, credit lines, or seasonality, and the “typical” bands quoted here are textbook conventions that vary widely by industry. Nothing here is investment, credit, or accounting advice.