# Bid-Ask Calculator

> Calculate bid-ask spread, midpoint, spread percentage, and trade values for a quoted security.

Page: https://askcalculators.com/calculator/bid-ask-calculator/
Definition: https://askcalculators.com/calculator/bid-ask-calculator/definition.json
JSON Schema: https://askcalculators.com/calculator/bid-ask-calculator/schema.json
Version: 1.0.0
Maintained by: AskCalculators (software project; not a credentialed reviewer)
Qualified review: pending. Automated checks do not establish professional approval.
Page status: Live
Review status: Pending

## Use
Open the calculator page and enter values. Query-string parameters can restore and bookmark a calculation.
Example: https://askcalculators.com/calculator/bid-ask-calculator/?bidPrice=99.5&askPrice=100.1&quantity=100

## Inputs
- bidPrice: Bid price; type=money; required; default=99.5; min=0
- askPrice: Ask price; type=money; required; default=100.1; min=0
- quantity: Quantity; type=number; required; default=100; min=0

## Outputs
- spread: Bid-ask spread; format=currency; primary
- spreadPercentMidpoint: Spread as % of midpoint; format=percent
- midpoint: Quote midpoint; format=currency
- buyValue: Cost to buy at ask; format=currency
- sellValue: Proceeds to sell at bid; format=currency
- roundTripSpreadCost: Immediate spread cost; format=currency

## Formula
spread = ask − bid; spread % = spread ÷ midpoint × 100%

## Rules
- Empty optional inputs are undefined, not zero.
- Hidden conditional inputs are ignored.
- Do not invent missing required inputs.

Notice: Market quotes can change rapidly. This calculator does not provide investment advice or executable pricing.