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Days to cover calculator.

Calculate the short interest ratio from reported shares sold short and average daily volume. Add public float to see short interest as a percentage of tradable shares.

Enter reported inputs

Use the latest reported short-interest position in shares.
Use a clearly defined averaging window and keep it consistent when comparing periods.
Used only to calculate short interest as a percentage of float.

Calculated liquidity ratios

days to cover
Short interest / float
At 2× average volume
At 3× average volume

The volume scenarios are arithmetic comparisons, not estimates of future volume or covering behaviour.

Days to cover formula

Days to cover = reported shares sold short ÷ average daily share volume

FINRA’s glossary defines days to cover—also called the short interest ratio—using this formula. Short interest as a percentage of float is calculated separately: shares sold short ÷ public float × 100.

The 2× and 3× figures divide the same reported short position by hypothetical volume multiples. They show mathematical sensitivity only; actual volume includes every market participant and can change sharply.

What the result does—and does not—say

Important: this ratio does not predict whether, when, or at what price short sellers will cover. Reported short interest is a delayed position snapshot, while daily short-sale volume is a different measure. Check every input’s source and as-of date.

FINRA’s Equity Short Interest Glossary defines the ratio. FINRA’s investor explainer distinguishes short interest from daily short-sale volume. For broader context, combine the result with the short squeeze pressure calculator.

VisionBoard Finance is informational and educational only. Nothing on this page is individualized investment advice.