Thunderbolt 3 Cable: Speed & Compatibility Guide
By Shop iPhone 17 Chargers, Screen Protectors & More | Belkin US | Published: 2026-10-25
Category: Buying Guides
Learn what Thunderbolt 3 cables offer in speed and power delivery, and how they compare to standard USB-C cables for your devices.
Quick answer
A Thunderbolt 3 cable like the Belkin Thunderbolt 3 Cable gives you up to 40Gbps data transfer and 100W power delivery, but it's only needed if your devices support Thunderbolt 3.
Why speed matters for your workflow
Thunderbolt 3 cables handle up to 40Gbps, which is four times faster than standard USB 3.1 Gen 2. This matters if you regularly transfer large video files, back up drives, or connect multiple 4K displays.
For everyday charging and syncing a phone or tablet, you won't notice the extra speed. A standard USB-C cable is more than enough for those tasks.
Power delivery capabilities
Both Thunderbolt 3 and many USB-C cables support up to 100W power delivery. That means you can charge a laptop, tablet, or phone with the same cable.
The Belkin Thunderbolt 3 Cable handles 100W and 5A, so it works with high-power devices like a MacBook Pro or Dell XPS. If you only charge smaller devices, a lower-wattage cable is fine.
Compatibility considerations
Thunderbolt 3 cables are backward compatible with USB-C ports, but they only run at Thunderbolt speeds when connected to Thunderbolt 3 ports on both ends.
If you plug a Thunderbolt 3 cable into a standard USB-C port, it will work but at USB-C speeds. You won't get the 40Gbps benefit. Check your device specs before buying.
Decision rules for choosing a Thunderbolt 3 cable
- Check device support: Look for a Thunderbolt 3 logo or specification on your laptop, dock, or monitor. If neither device supports Thunderbolt 3, a standard USB-C cable works fine.
- Match power needs: If you need to charge a laptop, ensure the cable supports at least 60W (or 100W for larger laptops). The Belkin Thunderbolt 3 Cable delivers 100W.
- Consider cable length: Thunderbolt 3 cables are typically limited to 0.8m (2.6 ft) for full 40Gbps speed. Longer cables may drop to 20Gbps. Check length specs before buying. For desk setups, a 0.8m cable is often sufficient. For longer runs, consider active cables or Thunderbolt 4 options.
Product facts
- Thunderbolt 3 Cable (USB-C to USB-C, 100W): Supports Thunderbolt 3 speeds of up to 40Gbps for fast data transfer and handles up to 100W power delivery. This means you can transfer large files quickly and charge a laptop with a single cable, reducing desk clutter.
Thunderbolt 3 Cable (USB-C to USB-C, 100W)
Who should buy a Thunderbolt 3 cable
Best for
- Professionals transferring large video or design files between a Thunderbolt 3 laptop and external drive
- Users who want to daisy-chain multiple 4K monitors or eGPUs with a single cable
Not for
- Everyday phone or tablet charging – a standard USB-C cable is cheaper and sufficient
- Users with only USB-C ports and no Thunderbolt 3 devices – you won't see speed benefits
