Every USB-C charger listing now says GaN somewhere on it, usually next to a claim about charging faster. Half of that is real engineering and half is marketing. Here’s the difference.
The actual technology, briefly
Inside every mains charger are switching transistors that chop 230V AC mains into something your laptop can use. For decades those have been silicon. GaN chargers use gallium nitride instead.
Gallium nitride has a wider bandgap than silicon, which means it tolerates higher voltages across a thinner layer of material and switches on and off much faster with less energy lost as heat each time.
Switching faster is the key. The transformer and capacitors in a power supply can shrink as switching frequency rises, because they’re storing energy for shorter intervals. Higher frequency plus lower switching losses gets you a physically smaller charger that runs cooler at the same output.
What GaN genuinely gives you
| Traditional silicon charger | GaN charger | |
|---|---|---|
| Size at the same wattage | Larger — think the old laptop brick | Noticeably smaller, often half the volume |
| Heat | Warmer, more energy lost in conversion | Cooler under the same load |
| Efficiency | Good | Slightly better, more so at high output |
| Charging speed | Identical if both support the same USB PD profiles | |
| Safety | Comes from design and certification, not from the semiconductor | |
| Price | Cheaper at low wattages | Small premium, narrowing every year |
Read those last two rows carefully, because they’re the ones the marketing tends to skip.
The myth: “GaN charges faster”
It doesn’t, on its own. Charging speed is set by USB Power Delivery negotiation — your device asks for a voltage and current, the charger agrees or offers the next one down, and they settle. A 65W GaN charger and a 65W silicon charger delivering the same PD profiles will charge your laptop at exactly the same rate.
The reason GaN feels faster is a selection effect: high-wattage multi-port chargers are almost all GaN now, because building 100W into a pocket-sized housing with silicon isn’t practical. People upgrade from an old 30W brick to a 100W GaN unit and credit the gallium nitride, when the wattage did the work.
So when you’re comparing chargers, compare the PD output profiles, not the semiconductor. A charger listing that shows its full profile list — 5V/3A, 9V/3A, 12V/3A, 15V/3A, 20V/5A, for example — is telling you exactly what it can do at every step.
What to actually check before buying, in Australia
1. The RCM mark
Mains-powered chargers sold in Australia sit under the national electrical equipment safety framework, and the Regulatory Compliance Mark is the visible sign that a supplier has taken responsibility for that. This is not a nice-to-have on a device that lives in a wall socket in your house. Our 100W GaN USB-C charger is RCM certified for AU/NZ.
Be sceptical of very cheap no-name chargers from overseas marketplaces. The ACCC has run repeated warnings about unapproved chargers and adapters, and the failure mode isn’t a slow charge — it’s a fire risk.
2. The plug
Australia and New Zealand use the Type I plug on 230V, 50Hz mains. A charger built for the local market has that plug moulded in. A charger with a US plug and a bundled travel adapter is a compromise that hangs badly out of the wall and gets knocked loose.
3. Input voltage range
Look for 100–240V input. That means it works on Australian mains and everywhere else you’ll travel with only a plug adapter, no voltage converter. Our 100W model takes 100–240V at 50/60Hz.
4. Protection circuitry
Over-current, over-voltage, short-circuit and over-temperature protection are the standard four. The 100W model lists all four (OCP, OVP, SCP, OTP); our 65W USB-C GaN charger lists over-current, over-temperature and over-charge protection.
5. PPS, if you own a recent Samsung
PPS (Programmable Power Supply) lets a device request voltage in fine increments instead of fixed steps, which is what recent Galaxy phones use for their fastest charging mode. If there’s no Samsung in the house, it’s a nice extra rather than a deciding factor.
When a GaN charger is not worth buying
Genuinely, plenty of the time:
- You only charge a phone. A 20–30W charger handles any phone on the market. Spending $100 on 100W to charge an iPhone achieves nothing.
- Your current charger is fine. GaN won’t extend your battery life, charge faster at the same wattage, or improve anything you’d notice beyond size and warmth.
- You want it purely for the badge. A well-made silicon 30W charger from a reputable brand beats a suspiciously cheap 100W GaN one every time.
The good reasons are specific: replacing several bricks with one charger, wanting something small enough to live in a bag permanently, or needing 65W–100W for a laptop where a compact silicon equivalent doesn’t really exist.
Matching wattage to what you own
| What you’re charging | Sensible wattage | Notes |
|---|---|---|
| Phone only | 20–30W | More wattage changes nothing |
| Phone + tablet | 30–45W | Multi-port is more useful than more watts |
| MacBook Air, ultrabook | 65W | Comfortable headroom for everyday use |
| 14″ MacBook Pro, workstation laptop | 65–100W | 100W if you run it hard for hours |
| 16″ MacBook Pro at full fast-charge | 140W | Needs USB PD 3.1; 100W won’t reach it |
Don’t forget the cable
A charger above 60W is only as good as the cable feeding it through. USB-C cables without a 5A e-marker chip are capped at 60W, so a 100W charger with the wrong cable quietly delivers 60W and you’d never know. A USB-C to USB-C cable rated for 100W/5A removes that bottleneck — and if it also does 10Gbps data, it doubles as a drive cable.
FAQs
Is a GaN charger safer than a normal one?
Not inherently. GaN runs cooler, which helps, but safety comes from the design, the protection circuitry and the certification behind it. Check for the RCM mark rather than the word GaN.
Will a GaN charger charge my phone faster?
Only if it supports a higher-wattage or better-matched USB PD profile than your old charger. At the same wattage and profiles, the charging speed is identical.
Do GaN chargers work with any device?
Yes. They use standard USB-C and USB Power Delivery, so they work with phones, tablets, laptops, headphones and handheld consoles. The device negotiates what it needs.
Why does my GaN charger still get warm?
All power conversion produces heat, and a small housing has less surface area to shed it. Warm is normal; too hot to hold comfortably, or a smell of hot plastic, means stop using it.
Can I leave a GaN charger plugged in all the time?
A certified charger from a reputable supplier is designed for it, and modern chargers draw very little at idle. As with any mains device, use a socket you can see and don’t cover it with bedding or paper.
If you’re replacing a charger
Decide on wattage first, confirm the RCM mark and the Australian plug, then check the cable can carry it. Our chargers ship from Australia in 2–5 business days with a local warranty and a proper tax invoice, and there’s a 30-day money-back guarantee if you end up wanting a different size.
