速动比率是指速动资产对流动负债的比率。它是衡量企业流动资产中可以立即变现用于偿还流动负债的能力。Investopedia中对其是这样定义的“The acid-test, or quick ratio, compares a company's most short-term assets to its most short-term liabilities to see if a company has enough cash to pay its immediate liabilities, such as short-term debt. ”。

速动资产包括货币资金（Cash）、短期投资（Short-term Investment）、应收票据（Notes Receivable）、应收账款（Accounts Receivable）、其他应收款项（Other Accounts Receivable）等，可以在较短时间内变现。而流动资产中存货、1年内到期的非流动资产及其他流动资产等则不应计入。　

速动比率的计算公式为：

Acid Test = (Cash+Marketable Securities +Accounts receivable)/Current Liabilities

速动比率=（货币资金+交易性金融资产+应收账款）/流动负债

速动比率在一些情况下要比流动比率Current Ratio（流动资产对流动负债的比率，用来衡量企业流动资产在短期债务到期以前，可以变为现金用于偿还负债的能力）更为有用，因为它忽视了一些难以尽快变现的资产，如库存。

以下为相关示例：

例1：

This paper discover: (1)The sustainable growth rate of a public company is in inverse proportion to asset-debt ratio, but in direct proportion to current debt ratio as well as acid test ration.

分析结果表明：1）公司可持续增长率与资产负债率成反比，与流动比率、速动比率成正比。

例2：

It is also called acid test ratio which is calculated by deducting inventories from current assets and then dividing the remainder by current liabilities.

也称为酸性测试比率，是现金类资产对流动负债的比率关系。