Best USB Voltmeter for Checking Chargers and Ports
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A USB voltmeter is a small meter that reads voltage at a USB port or charger, which makes it handy for phone chargers, power banks and low-voltage projects. All six listings below plug into a USB port or cable path. All six also show current, and three list capacity.
The most useful checks are the voltage and current range, and which connector you need: USB-A, USB-C or both. Where a listing does not state a range, weight or size, this guide says not stated. Keep USB testing to low-voltage sources and follow the maker instructions.
Quick answer
For USB-C testing with a stated range, the YOJOCK and the YEREADW both give 4-30V and 0-12A in their titles. The Klein Tools ET920 covers both USB-A and USB-C and also lists capacity, energy and resistance, but its range is not stated in the fields shown. The Eversame is a 2 in 1 Type C tester with a color LCD, weighing 1.1 ounces. For USB-A only, look at the diymore.
Comparison table
| Product | Connector | Stated range | Other readings | Weight |
|---|---|---|---|---|
| YOJOCK 360W | USB-C (Type-C PD) | 4-30V, 0-12A, 360W | Power bank capacity | 0.04 kg |
| YEREADW | USB-C (Type-C PD) | 4-30V, 0-12A | Power bank capacity | Not stated |
| Klein Tools ET920 | USB-A and USB-C | Not stated | Voltage, current, capacity, energy, resistance | 1.76 ounces |
| Eversame 2 in 1 | Type C | Not stated | Voltage and current on a color LCD | 1.1 ounces |
| FORIOT 2Pcs | USB-C and USB port | Not stated | DC voltage and current, blue and red display | Not stated |
| diymore | USB A (title also mentions USB C) | Not stated | Voltage and current | Not stated |
Product reviews
YOJOCK 360W USB C Tester Power Meter
What it is: A grey-blue Type-C PD tester powered through USB and Type-C. The title gives 360W, 4-30V and 0-12A, and says it also shows power bank capacity. Weight is 0.04 kg.
Who it suits: Someone testing USB-C chargers, cables or power banks who wants a stated range.
- Pros: Voltage, current and power ratings are in the title. Light.
- Cons: Dimensions and plug layout are not stated.
Skip if: You only use USB-A ports.
YOJOCK USB C tester on Amazon (affiliate link)
YEREADW USB C Tester Power Meter
What it is: A silver-grey Type-C PD tester powered through USB and Type-C. The title gives 4-30V and 0-12A and says it reads voltage, current and power bank capacity. Measurement type is listed as multimeter.
Who it suits: A buyer who wants the same stated range as the YOJOCK in a different body.
- Pros: Range is in the title. Capacity reading is named.
- Cons: Weight and dimensions are not stated.
Skip if: You need to know its size before ordering.
YEREADW USB C tester on Amazon (affiliate link)
Klein Tools ET920 USB Power Meter
What it is: An orange meter powered from the USB port, with a USB-A and USB-C style. The title lists voltage, current, capacity, energy and resistance. Weight is 1.76 ounces.
Who it suits: Someone who tests both USB-A and USB-C gear and wants energy and resistance readings too.
- Pros: Covers both connector types. The widest list of readings here.
- Cons: No voltage range is quoted in the fields shown.
Skip if: You need a stated voltage and current range up front.
Klein Tools ET920 on Amazon (affiliate link)
Eversame 2 in 1 Type C USB Tester
What it is: A black Type C USB tester with a color LCD screen that reads voltage and current. Power source is listed as electric, style as voltage tester, and weight as 1.1 ounces.
Who it suits: A buyer who wants a light USB-C tester with a color screen.
- Pros: Color LCD. Lightest weight quoted in this group.
- Cons: No voltage range is quoted in the fields shown.
Skip if: You need a stated range, or you only use USB-A.
Eversame USB tester on Amazon (affiliate link)
FORIOT 2Pcs USB Tester
What it is: A black DC USB meter with a blue and red display, sold as a 2Pcs set per the title. The fields list ammeter and voltmeter measurement types and battery power.
Who it suits: Someone who wants two simple meters, for example one for a charger and one for a cable, once the product page confirms the pack contents.
- Pros: Two meters in the title. Shows voltage and current.
- Cons: No range, weight or size is stated.
Skip if: You need power bank capacity or a stated range.
FORIOT USB tester on Amazon (affiliate link)
diymore USB Tester
What it is: A USB port tester and battery checker for USB A. The fields list ammeter, multimeter and voltmeter types and battery power. The title also mentions USB C.
Who it suits: A buyer with USB-A chargers who wants basic voltage and current readings.
- Pros: Voltage and current readings are named. The title names it a battery checker.
- Cons: No range, weight or size is stated. The color field reads USB A Tester instead of a color.
Skip if: You need a stated range or a confirmed USB-C fit.
diymore USB tester on Amazon (affiliate link)
Buying checklist
- Match the connector: USB-A, USB-C or both.
- Check the voltage and current range against your charger or power bank.
- Decide whether you want capacity, energy or resistance readings.
- Check size on the product page where dimensions are not stated.
- Read the exact variant page for power source, color and weight.
- Use USB meters on low-voltage sources only.
FAQ
What does a USB voltmeter measure?
It reads the voltage at a USB port or cable. Most listings here also read current, and some show capacity, energy or resistance.
Which listings state a voltage and current range?
The YOJOCK and the YEREADW both state 4-30V and 0-12A in their titles. The others do not quote a range in the fields shown.
Can I test both USB-A and USB-C?
The Klein Tools ET920 is listed for USB-A and USB-C. The YOJOCK, YEREADW and Eversame are Type-C testers, and the diymore is for USB A.
Is a USB voltmeter safe for wall outlets?
No. These are low-voltage USB tools. For mains voltage, use a meter with a stated CAT rating and follow its manual.
What does the 2Pcs in the FORIOT title mean?
The title says 2Pcs, so it appears to be a set of two meters. Check the product page to confirm the pack contents.
Closing note
Choose by connector first and range second, then check size on the product page. Related guides on neighboring tests: Best Test Light with Voltmeter, Best Test Outlet with Voltmeter and Best Testing a Capacitor with a Voltmeter. For safety ratings, see the measurement category overview.
