Results and Conclusion

Fast charging standards compared

To test our array of fast charging phones, we selected devices with reasonably similar battery sizes - they're all around 3,000mAh. We fully drained the batteries of each phone, then plugged them one-by-one into the same wall socket, taking power recordings every ten minutes. Our office is air conditioned, so the environmental temperature is fairly constant. All phones remained off for the duration of the charging.

	Apple iPhone X (256GB)	ASUS ZenFone 5 (2018)	Huawei P20	LG G7+ ThinQ	OnePlus 6 (6GB/64GB)	Samsung Galaxy S9	Oppo R15 Pro
Operating system	iOS 11.1	Android 8.0 Oreo with ZenUI 5.0	Android 8.1 with EMUI 8.1	Android 8.0 Oreo with LG UX 6.0	Android 8.1 Oreo with Oxygen OS	Android 8.0 Oreo with Samsung Experience	Android 8.1 Oreo with Color OS
Processor	Apple A11 Bionic hexa-core	Qualcomm Snapdragon 636 Octa-core (8 x Kryo 260)	Hisilicon Kirin 970 octa-core (4x2.4 GHz Cortex-A73 & 4x1.8 GHz Cortex-A53)	Qualcomm Snapdragon 845 Octa-core (4 x 2.8GHz Kryo 385 Gold & 4 x 1.7GHz Kryo 385 Silver)	Qualcomm Snapdragon 845 Octa-core (4 x 2.8GHz Kryo 385 Gold & 4 x 1.7GHz Kryo 385 Silver)	Samsung Exynos 9810 octa-core (4x2.8 GHz Mongoose M3 & 4x1.7 GHz Cortex-A55)	Qualcomm Snapdragon 660 Octa-core (4x2.2 GHz Kryo 260 & 4x1.8 GHz Kryo 260)
Built-in Memory	3GB RAM	4GB RAM	6GB RAM	6GB RAM	6GB RAM	4GB RAM	6GB RAM
Display	5.8-inch Super Retina HD / 2,436 x 1,125 pixels (458ppi) / OLED	6.2-inch / 2,246 x 1,080 pixels (402 ppi) / 18.7:9 aspect ratio / IPS LCD	5.8-inches 2,244 x 1,080 pixels (428 ppi) AMOLED 18.7:9 ratio	6.1-inch / 3,120 x 1,440 pixels (564ppi) / 19.5:9 ratio / IPS LCD Always-on Display	6.28-inch / 2,280 x 1,080 pixels (402ppi) / 19:9 ratio / Optic AMOLED Always-on Display	5.8-inch / 2,960 x 1,440 pixels (570 ppi) / 18.5: 9 ratio / Super AMOLED Infinity Display Always-On Display	6.28-inch / 2,280 x 1,080 pixels (401 ppi) / 19:9 aspect ratio / AMOLED
Camera	Rear: Dual 12-megapixel, (f/1.8, 28mm & f/2.4, 56mm) with phase detection autofocus, OIS, and quad LED (dual-tone) flash Front: 7-megapixel, f/2.2 FaceTime HD camera	Rear: 12-megapixel f/1.8 with 4-axis OIS + wide-angle 8-megapixel f/2.0 Front: 8-megapixel f/2.0	Rear: Dual 12-megapixel f/1.8 monochrome, 1/2.3" OIS + 20-megapixel f/1.6 RGB, Leica optics, phase detection and laser autofocus, dual-LED dual-tone flash Front: 24-megapixel, f/2.0	Rear: Dual: 16-megapixel f/1.6, OIS + 16-megapixel f/1.9 wide-angle Front: 8-megapixel, f/1.9	Rear: Dual: 16-megapixel (f/1.7, 27mm, 1/2.6", 1.22µm, OIS) + 20-megapixel (f/1.7, 1/2.8", 1.0µm), Front: 16-megapixel (f/2.0, 25mm, 1/3", 1.0µm)	Rear: 12-megapixel, dual f/1.5 and 2.4, 26mm, Dual Pixel PDAF, OIS, LED flash Front: 8-megapixel, f/1.7	Rear: 16-megapixel f/1.7 + 20-megapixel f/1.7, 2x optical zoom Front: 20-megapixel, f/2.0
Connectivity	Wi-Fi 802.11 a/b/g/n/ac, 4G+ LTE Cat 12 (up to 600Mbps), dual-band, hotspot, Bluetooth v5.0, A2DP, LE, GPS, GLONASS, Lightning connector	Wi-Fi 802.11 a/b/g/n/ac, dual-band, WiFi Direct, hotspot, Bluetooth 5.0, A2DP, LE, EDR, GPS, GLONASS, NFC	Wi-Fi 802.11 a/b/g/n/ac, 4G+ LTE-A (3CA) Cat 18 (up to 1200Mbps), dual-band, hotspot, Bluetooth v4.2, A2DP, LE, GPS, GLONASS, USB 3.1 Type-C	Wi-Fi 802.11 a/b/g/n/ac, dual-band, DLNA, WiFi Direct, Bluetooth v5, NFC, 4G LTE Cat 16 (up to 1024Mbps)	Wi-Fi 802.11 a/b/g/n/ac, dual-band, DLNA, WiFi Direct, Bluetooth v5, NFC, 4G LTE Cat 16 (up to 1024Mbps)	Wi-Fi 802.11 a/b/g/n/ac (2.4 + 5GHz), 4G+ LTE Cat 18 (up to 1200Mbps), Bluetooth 5.0, VHT80, MIMO (2x2), GPS, GLONASS, NFC, Screen Mirroring	Wi-Fi 802.11 a/b/g/n/ac, dual-band, WiFi Direct, hotspot, Bluetooth 4.2, A2DP, LE, EDR, GPS, GLONASS, LTE Cat 6 (up to 300Mbps)
Storage Type	256GB internal storage	64GB internal storage Expandable up to 256GB (via microSD shared with SIM 2 slot)	128GB internal storage	128GB internal storage Expandable up to 2TB via microSD	64GB	64GB internal storage 256GB (MicroSD)	128GB internal storage Expandable up to 256GB (via microSD shared with SIM 2 slot)
Battery	2,716mAh	3,300mAh	3,400mAh	3,000mAh Quick Charge 3 Wireless charging	3,300mAh Dash Charge	3,000mAh Samsung Adaptive Fast Charging Wireless charging	3,430mAh
Dimensions	143.6 x 70.9 x 7.7 mm	153 x 75.7 x 7.9 mm	149.1 x 70.8 x 7.7 mm	153.2 x 71.9 x 7.9mm	155.7 x 75.4 x 7.8 mm	147.7 x 68.7 x 8.5 mm	156.5 x 75.2 x 8 mm
Weight	174g	155g	165g	162g	177g	163g	180g

Performance findings

The three fast charging standards that stood out from the rest were Oppo's VOOC Charge, OnePlus' Dash Charge, and Huawei's Super Charge. The Oppo R15 Pro had the most charge at ten minutes, with an amazing 28 percent charge, with the P20 just behind at 26 percent and the OnePlus 6 at 25 percent. At the 30 minute mark, all three phones were over 60 percent charge, with the P20 in the lead at 68 percent.

The first phone to reach 100 percent charge was the Huawei P20, doing it in just 54 minutes. It was closely followed by the OnePlus 6 at 62 minutes, and the Oppo R15 Pro at 65 minutes. The iPhone X charged the slowest, taking 102 minutes to reach full charge, and that's despite having the smallest battery in this shootout. To cut the story short, we don't think Apple's charging goal at this point is to get the iPhone's battery from 0 to 100 percent in the shortest amount of time. Rather, we observed the charger delivering more power at the early stages of charging, with the aim to get the phone to a 50 percent charge in 30 minutes. As such, if you aren't using the iPhone 8 Plus, the more affordable iPad 12W charger is actually good enough to quick charge the iPhone X and 8.

Conclusion

With battery capacities getting larger and larger, fast charging is now almost a requirement on a modern smartphone. Fortunately, fast charging standards are constantly improving and most phones with fast charging will now give you at least 50 percent charge in just 30 minutes. 

Compared to three years ago, we can see how fast charging has improved, and there's significantly less drop off in charging speed now, with most phones maintaining a fairly fast charge throughout the entire charge process. Previously, we saw a big drop off in charging speed after about 40 percent or so.

The next big breakthrough in fast charging looks to be Oppo's Super VOOC charging standard, which was first teased back in 2016, but is only now reaching smartphones, and is currently only available on the 256GB Oppo Find X, which will be released in Singapore later this year, and the limited edition Lamborghini edition Find X, which unfortunately won't be available here. However it promises to deliver a full charge in just 15 minutes of charging. We'll update this feature when we can test it out for ourselves.

Finally, a quick note on wireless charging. Wireless charging is always slower than a wired fast charger, however, we've also seen improvements here. Samsung's wireless fast charger will charge the S9 from 0 to 100 percent in 139 minutes, which, while notably slower than the standard wired connection, is still quite fast. If you want the fastest possible charge time though, stick to your wired connection.

In this shootout however, the winner is the Huawei SuperCharge, which managed to top up the Huawei P20's sizeable 3,400mAh battery in just 54 minutes.