The difference between current ratio and quick ratio is that the former includes inventory in its equation, while the latter does not. Current ratio measures the liquidity of a company by dividing the current assets by the current liabilities. The quick ratio does essentially the same thing, but can be used when the inventory attached to the company is of a variable value. Assessing the long-term value of inventory can help an analyst when deciding between current ratio and quick ratio as a means of determining company liquidity.