---
title: maxTransferRate
framework: metal
role: symbol
role_heading: Instance Property
path: metal/mtldevice/maxtransferrate
---

# maxTransferRate

The highest theoretical rate, in bytes per second, the system can copy between system memory and the GPU’s dedicated memory (VRAM).

## Declaration

```swift
var maxTransferRate: UInt64 { get }
```

## Discussion

Discussion Metal calculates this value from the raw data-clock rate, and the GPU may not be able to reach this speed in real-world conditions. important: The maximum transfer rate for built-in GPUs is 0.

## See Also

### Checking a GPU device’s memory

- [currentAllocatedSize](metal/mtldevice/currentallocatedsize.md)
- [recommendedMaxWorkingSetSize](metal/mtldevice/recommendedmaxworkingsetsize.md)
- [hasUnifiedMemory](metal/mtldevice/hasunifiedmemory.md)