Smart Buyer #4: Phone charger — watts, USB PD and why the cable matters
Watts = volts × amps (5 V × 1 A = 5 W is slow; most phones want 20 W+); USB PD agrees on a higher voltage (5 · 9 · 15 · 20 V) and a bigger charger is safe; a thin cable gets warm and slow — pick a 3 A USB-C cable with a safety mark (UL · CE/UKCA · BIS).
Buying a phone charger? 🔌 Check these 3 things before you pay 👇
1️⃣ WATTS: watts = volts × amps. The old cube: 5 V × 1 A = only 5 W (slow!). Most phones today charge at 20 W or more — check your phone's max first.
2️⃣ USB PD (Power Delivery): the phone and charger agree on a higher voltage (5 · 9 · 15 · 20 V), so it charges much faster. A bigger charger (say 65 W) is safe — the phone only takes what it needs.
3️⃣ THE CABLE: a thin, cheap cable has tiny copper wires — it gets warm and slows charging down. Pick a 3 A USB-C cable (good for up to 60 W) with a safety mark: UL (USA) · CE / UKCA (Europe/UK) · BIS (India). Skip fake no-name chargers.
Check watts, PD, cable! ✅
Read the voiceover (transcript)
- Buying a phone charger?
- One: watts! Volts times amps. Five volts, one amp is only five watts. Most phones want twenty watts or more.
- Two: USB PD. The phone and charger agree on a higher voltage, so it charges fast. A bigger charger is safe.
- Three: the cable! A thin, cheap cable gets warm and slows it down. Pick a three amp cable with a safety mark.
- Check watts, PD, cable!
- Next: what can your power strip really handle? Follow for more!
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