# Floating-Point Operators for Double Perform arithmetic and bitwise operations or compare values. ## Topics ### Arithmetic [`static func + (Double, Double) -> Double`](/documentation/Swift/Double/+(_:_:)) Adds two values and produces their sum, rounded to a representable value. [`static func - (Double, Double) -> Double`](/documentation/Swift/Double/-(_:_:)) Subtracts one value from another and produces their difference, rounded to a representable value. [`static func * (Double, Double) -> Double`](/documentation/Swift/Double/*(_:_:)) Multiplies two values and produces their product, rounding to a representable value. [`static func / (Double, Double) -> Double`](/documentation/Swift/Double/_(_:_:)) Returns the quotient of dividing the first value by the second, rounded to a representable value. ### Arithmetic with Assignment [`static func += (inout Double, Double)`](/documentation/Swift/Double/+=(_:_:)) Adds two values and stores the result in the left-hand-side variable, rounded to a representable value. [`static func -= (inout Double, Double)`](/documentation/Swift/Double/-=(_:_:)) Subtracts the second value from the first and stores the difference in the left-hand-side variable, rounding to a representable value. [`static func *= (inout Double, Double)`](/documentation/Swift/Double/*=(_:_:)) Multiplies two values and stores the result in the left-hand-side variable, rounding to a representable value. [`static func /= (inout Double, Double)`](/documentation/Swift/Double/_=(_:_:)) Divides the first value by the second and stores the quotient in the left-hand-side variable, rounding to a representable value. ### Comparison [`static func == (Self, Self) -> Bool`](/documentation/Swift/Double/==(_:_:)-12hdv) Returns a Boolean value indicating whether two values are equal. [`static func != (borrowing Self, borrowing Self) -> Bool`](/documentation/Swift/Double/!=(_:_:)) Returns a Boolean value indicating whether two values are not equal. ### Negation [`static func - (Double) -> Double`](/documentation/Swift/Double/-(_:)) Calculates the additive inverse of a value. [`static func + (Self) -> Self`](/documentation/Swift/Double/+(_:)) Returns the given number unchanged. ### Range Expressions [`static func ... (Self) -> PartialRangeThrough`](/documentation/Swift/Double/...(_:)-4mm67) Returns a partial range up to, and including, its upper bound. [`static func ... (Self) -> PartialRangeFrom`](/documentation/Swift/Double/...(_:)-6ct5v) Returns a partial range extending upward from a lower bound. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)