If you're in a rush, wired charging is still the way to go. Most of the best smartphones will charge quicker using the power adapter that comes in the box than using wireless charging - despite its recent resurgence thanks to Apple.

Many companies, especially Chinese phone brands, are now pushing the boundaries of wired charging, including super-fast chargers in the box, with promises of a lightning fast recharge. 

The one we are really interested in is Oppo's Super VOOC flash charging. Oppo claims that just 20 minutes plugged into its adapter is enough to get you a day's worth of power. But how does this compare to other fast chargers? 

The phones

The testing method

Instead of coming up with some sterile scientific charging scenario, we decided the best way to compare them for the average consumer would be to plug all the phones in at the same time - having drained them to zero beforehand - and then stopping at exactly the same time and seeing how battery levels compared. That required a simple multi-socket power strip with a built in on/off switch. 

We wanted to see how much charge was in the phones after 5, 10 and 20 minutes of being plugged in, and after that running a stopwatch to see which reached its full capacity first. 

After 5 minutes...

In previous years, plugging in your phone for just 5 minutes would prove utterly fruitless, but with Oppo's Super VOOC technology, it should theoretically have delivered a useful amount of power to the phone in that time. It didn't disappoint. 

  • OnePlus 6T - Too low to turn on
  • Google Pixel 3 - 5 per cent
  • OnePlus 6T McLaren Edition - 12 per cent
  • Huawei Mate 20 Pro - 11 per cent
  • Oppo RX17 Pro - 22 per cent

While the standard OnePlus 6T didn't have enough juice to even power on, the Pixel 3 - which has the smallest battery of the lot - was up to a minuscule 5 per cent. On the other hand, the newer, more powerful charging tech had delivered considerably more. The McLaren Edition OnePlus 6T - with its more powerful adapter - was up to 12 per cent. Huawei's more capacious Mate 20 Pro battery was around 11 per cent. 

As for the Oppo RX17 Pro, it turns out Super VOOC is as amazing as Oppo says it is. The phone was already up to 22 per cent. After 5 minutes!  

After 10 minutes...

Having started off so well, we were excited to see how much more juice Super VOOC could deliver in another 5 minutes. Here's how the phones were looking after 10 minutes of being plugged in: 

  • OnePlus 6T - 7 per cent
  • Google Pixel 3 - 12 per cent
  • OnePlus 6T McLaren Edition - 24 per cent
  • Huawei Mate 20 Pro - 26 per cent
  • Oppo RX17 Pro - 43 per cent

Somehow, in just 10 minutes, the Oppo phone was heading towards the half full mark when its nearest competitor was barely over quarter full. With this much charge, the Oppo might already see you through a work day. It'll definitely last you an evening, even one loaded with social pics galore being snapped. 

After 20 minutes...

By the 20 minute mark, the Oppo's performance was starting to look downright ridiculous in comparison to the others. Which is saying something, because none of the others are really that slow at all. Here's how the phones compared at the 1/3 hour mark: 

  • OnePlus 6T - 24 per cent
  • Google Pixel 3 - 26 per cent
  • OnePlus 6T McLaren Edition - 47 per cent
  • Huawei Mate 20 Pro - 52 per cent
  • Oppo RX17 Pro - 76 per cent

With the Oppo now past the three quarters full line, its nearest competitors were just about half full, and the two phones using older charging tech were just about one quarter full. 

It's worth a quick reminder here that Huawei's battery is considerably larger than Oppo's. With an extra 500mAh to fill, that 52 per cent is actually around 2,184mAh. At this point, the Oppo - in comparison - was up to approximately 2,812mAh. 

To full capacity

With the Oppo already passed the three quarters mark, we were on to the final stretch and so instead of running down specific timers, we started a stopwatch to then see how long it took the phones to be fully charged. 

  • 1st - Oppo RX17 Pro - approx 38mins 28secs
  • 2nd - OnePlus 6T McLaren Edition - approx 1 hr 2mins 42secs
  • 3rd - Huawei Mate 20 Pro - approx 1 hr 6mins 25secs
  • 4th - OnePlus 6T - approx 1 hr 18mins 48secs
  • 5th - Google Pixel 3 - approx 1hr 42mins 20secs

Clearly then, the Oppo RX17 Pro is much faster than any of its current competitors when it comes to charging quickly. In under 40 minutes it was completely full and ready to roll. Its nearest rival in the end was the McLaren Edition OnePlus, which was still a good 24 minutes slower. 

The Huawei Mate 20 Pro was an interesting one. It's impressively quick to charge up, given how much extra battery capacity there is, but of all the phones, it was the one that seemed to slow down the most in the latter stages. At the point where the Oppo phone was full, the Huawei was up to 88 per cent, with the McLaren Edition phone behind on 81 per cent. But, by the time the hour mark had passed, the OnePlus had caught up, and eventually overtook it. 

As for the OnePlus 6T, this time last year, its then-called Dash Charge technology was the cream of the crop. Now, compared to this new generation of chargers it looks pretty average (despite actually being quite quick). It took more than twice as long than the Oppo RX17 Pro to fill up a battery that's the same size. 

Can I use any fast charger with my phone?

Sadly not, you can't just take any rapid charger and assume it's going to fill your phone at exactly the same speed. For instance, the Super VOOC flash charging won't top up a OnePlus 6T or Huawei Mate 20 Pro at the same speed. With proprietary methods, you often find it's either the type of port being use (USB 1.0, 2.0 or 3.0 as examples), other times it's the physical design of the battery, and still others it can involve the processor inside the phone as well. 

For instance, despite having a Type-C port and a Qualcomm processor, for years, OnePlus phones were never compatible with Quick Charge, and now aren't compatible with the standard Power Delivery (mentioned below). 

Apart from Chinese manufacturers who are creating their own rapid charging technology, there's a universal Power Delivery standard, often dubbed "PD" for short. And, unlike the proprietary Chinese methods, the output isn't limited to one single wattage. Pixel phones use 18W chargers, but bigger devices like MacBooks and some modern Windows laptops use Power Delivery as well, but at much higher wattages. 

What about the iPhone? How fast does that charge?

Out of the box, it only has the same standard 5W charger it's always come with, which means it takes considerable time to charge up with a cable, especially if you have a bigger model. But, for the past couple of years, it has been compatible with Power Delivery, meaning you can plug in a cable to your MacBook power adapter and have much faster fill-ups. The only downside here is that you need to buy a Type-C to Lightning cable. 

If you don't have a MacBook charger, there are ways around it that don't involve spending tonnes of money on a laptop power brick. For instance, picking up the 18W Pixel charger will do the trick, or even finding an external battery pack with built-in PD support. Of course, there's always wireless charging which - at 7.5W - is 50% faster than the bog standard cable method.