# CMTimeMakeWithSeconds(_:preferredTimescale:) Creates a time that represents a number of seconds in a preferred timescale. ``` func CMTimeMakeWithSeconds(_ seconds: Float64, preferredTimescale: Int32) -> CMTime ``` ## Parameters `seconds` The number of seconds to represent. `preferredTimescale` The preferred timescale of the time. ## Return Value A time structure. ## Discussion Specify a positive preferred timescale value, or the resulting time is [`invalid`](/documentation/CoreMedia/CMTime/invalid). If you specify a value that causes an overflow, the system repeatedly halves the value until the overflow goes away or the timescale equals `1`. If the value still overflows at that point, the system sets the value to positive or negative infinity. Query the [`hasBeenRounded`](/documentation/CoreMedia/CMTimeFlags/hasBeenRounded) property value to determine whether the value, when converted back to seconds, precisely matches the original seconds value. --- 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)