Use an Intel iMac as an external display for an Apple Silicon MacBook — free, no dongle, via Thunderbolt Bridge.

If TargetBridge is useful to you, a ⭐ on GitHub helps others find it.

Apple removed Target Display Mode on Apple Silicon. TargetBridge brings it back via software, streaming your MacBook screen to the iMac at up to 5K over a direct Thunderbolt cable.

Sender (MacBook Apple Silicon) — waiting for connection:

Sender — active stream (5K, HEVC):

Receiver (Intel iMac) — waiting for sender:

iMac connected at native resolution via Thunderbolt:

→ Download latest release (pre-built apps, no Xcode needed)

• TargetBridge.app.zip — Sender for MacBook Apple Silicon
• TargetBridge-Receiver.app.zip — Receiver for Intel iMac (requires macOS 14 Sonoma)

Unzip and double-click. On first launch, grant Screen Recording to the sender.

iMac on Ventura or older? The pre-built receiver requires macOS 14. Build it directly on your iMac instead — takes ~2 minutes, see the Quick Start guide.

Pre-built receiver crashing? Make sure you downloaded v1.1.0 or later — older builds required Homebrew. If you have an older build, re-download from the latest release.

• MacBook Apple Silicon (M1 or later) — sender
• Intel iMac 2017 or later — receiver
• Thunderbolt 3/4 cable

• 5K · 5120 × 2880 — native iMac 5K stream, HEVC, default
• Standard · 2560 × 1440 — lower latency fallback, scaled to fill the receiver

The sender can stream either an extended virtual display or a mirror of the MacBook display.

For an extended desktop, choose Extended display on the sender before connecting. After the virtual display appears, open macOS System Settings → Displays → Arrange on the sender Mac and position the external display where you want it.

If the receiver does not fill the iMac panel or the cursor/desktop feels scaled incorrectly, select the external TargetBridge display in macOS Display Settings and choose the matching resolution. For the 27-inch 5K iMac path, use the 5K stream profile with the external display set to the matching 5120 × 2880 / 2560 × 1440 HiDPI mode.

• TargetBridge-Sender
• TargetBridge-Receiver

• Italian: TargetBridge-QuickStart-IT.md
• English: TargetBridge-QuickStart-EN.md