Best multimeter with usb charging

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Updated 24 October 2026

Author: Ken

The best multimeter with USB charging is the one whose listing states a USB-C charging port, the measurements you need, and a CAT rating that suits your circuit. Work on mains circuits can kill, so check the CAT rating before you measure anything. Panel and service work belongs to a licensed electrician, and this guide gives no steps for working on live mains, outlets, panels or service wiring. Of the twelve listings in the scanned pool, four are multimeters or clamp meters that recharge over USB-C. The rest are USB-powered testers, a component tester or meters that run on ordinary batteries.

Quick answer

• Choose the FS899L 20-piece kit if you want a USB-C recharged multimeter with spare leads. Its listing states CAT III 1000V and CAT IV 600V.
• Choose the FS899L single-unit listing if you want the same ratings without the accessory set.
• Choose the NJTY T3 if you want a USB-C recharged multimeter with a 4000-count display and non-contact voltage detection. Its listing does not state a CAT rating, so do not use it on mains.
• Choose the FNIRSI DMC-100 if you need a clamp meter that charges over Type-C. Its listing states AC and DC current up to 600A but no CAT rating.
• Choose a USB tester such as the Klein ET920, the YOJOCK or the YEREADW only to check what a USB device draws or delivers. None of these listings states a CAT rating.

Charging a meter and measuring over USB are different jobs

Two kinds of product sit under this keyword, and the listings separate them clearly enough to tell apart. The first kind is a multimeter or clamp meter with its own rechargeable battery. The listing names a Type-C or USB-C port for charging that battery, and the meter works as a normal handheld instrument. The two FS899L listings, the NJTY T3 and the FNIRSI DMC-100 fall in this group.

The second kind is a USB tester. It plugs into a USB line, sits between a charger and a device, and reads voltage and current on that line. The Klein ET920 is an example. Its listing says it is powered from the USB port and connects in line between the source being measured and the power source. A USB tester does not need a charging port for its job, so a USB-C connector on one says nothing about whether it suits a mains circuit.

The distinction matters for the buyer. If you want a meter to check batteries, low-voltage wiring and small electronics on the bench, a USB-C recharged multimeter fits. If you want to see what a phone charger or power bank delivers, a USB tester fits better. Neither replaces the CAT check. For a wider look at hand-held meters in general, see the hand-held digital multimeter roundup.

Electrical safety first

Work on mains circuits can kill. Before you measure anything, check that the meter’s CAT rating suits the circuit you are testing, and read that rating from the listing or the manufacturer’s manual. Panel and service work belongs to a licensed electrician.

Fluke’s electrical learning hub warns that transients and surges are a real risk, and advises using test instruments rated for the voltage or current you are measuring. Fluke’s test lead article adds that measurement category ratings are set by the IEC 61010 safety standard and fall into four categories, CAT I through CAT IV. Read the category on each listing as a fixed label, not as a general promise of safety.

The US workplace rule for electrical work sets the same limit from the employer side. OSHA’s 29 CFR 1910.333 says that only qualified persons may work on electric circuit parts or equipment that have not been deenergized. It also requires that live parts an employee may be exposed to be deenergized before the employee works on or near them. This guide gives no step that asks you to work on live parts.

Battery care for rechargeable meters

Rechargeable meters carry a lithium cell, so battery handling is part of the safety picture. The Western Michigan University guidance on lithium-ion battery safety, written for lithium-ion cells, advises that you inspect batteries for damage before use and dispose of damaged ones promptly. It also warns against burning, disassembling or puncturing batteries. Stop using a meter whose battery shows damage, and follow the manufacturer’s charging instructions in the manual.

For how a voltage tester reads a battery, see how voltage testers work. That guide covers the reading itself, while this one covers the charging connector and the CAT rating.

Comparison table

The table uses only the figures each listing states. Where a listing is silent, the cell says so.

Pick	Type	Charging	Counts	CAT rating	Voltage and current
FS899L 20-piece kit	Multimeter	USB-C, about 2 hours	6000	CAT III 1000V, CAT IV 600V	DC and AC voltage 60mV to 600V; current 300mA to 10A
FS899L	Multimeter	USB-C, 2-hour charge	6000	CAT III 1000V, CAT IV 600V	Not stated
NJTY T3	Multimeter	Type-C port	4000	Not stated	Voltage and resistance; current not stated
FNIRSI DMC-100	Clamp meter	Type-C, 1500mAh battery	9999 in title, 10000 in a bullet	Not stated	AC and DC current up to 600A; voltage through test leads
Klein ET920	Inline USB meter	Powered from USB port	Not stated	Not stated	Voltage 3 to 20V DC; current 0.05 to 3A on USB-A, 0.05 to 5A on USB-C
YOJOCK	USB tester	Not stated	Not stated	Not stated	Voltage 3.6 to 32.0V; current 0 to 8.0A
YEREADW	USB tester	USB and Type-C power	Not stated	Not stated	Voltage 4 to 30V; current 0 to 12A

The picks

Pick 1: FS899L 20-piece kit

Best for: a bench multimeter that recharges over USB-C and comes with spare leads.

Strengths from the listing: The bullets state CAT III 1000V and CAT IV 600V, double fuses, 6000 counts with True RMS, and a 4.8-inch backlit screen. The listing says the battery charges in about 2 hours over USB-C and works for up to 8 hours. The bullets list alligator clips, test probes and adapters as part of a 20-piece accessory set.

Limits from the listing: The specification lines name only an instruction manual, which does not match the 20-piece set in the title and bullets. The listing does not state a warranty. Its current ranges are 300mA to 10A in the bullets, with a 10 A maximum on the specification lines, so check the figure against your job before you buy.

Skip if: you do not need the accessory set, or the circuit you plan to test is not covered by the CAT III 1000V or CAT IV 600V ratings the listing states.

Pick 2: FS899L

Best for: the same CAT ratings and USB-C charging without the accessory set.

Strengths from the listing: CAT III 1000V and CAT IV 600V appear in both the specification lines and the bullets. The bullets also state dual ceramic fuses, 6000-count True RMS readings, non-contact voltage detection, a 4.8-inch color screen, a built-in flashlight and Data Hold. The title mentions 2 alligator clips, and a bullet describes them as fully insulated. The bullets give a 2-hour USB-C charge.

Limits from the listing: The bullets do not give a current range, and the listing does not state a warranty. The specification lines name only an instruction manual as the included item.

Skip if: you need the spare probes and adapters that come with the 20-piece kit above.

Pick 3: NJTY T3

Best for: a USB-C recharged multimeter for low-voltage electrical checks, not for mains.

Strengths from the listing: 4000 counts, AC and DC voltage, resistance and continuity, non-contact voltage detection, a 3.2-inch color LCD and a battery-low indicator. The listing describes a Type-C charging port, an automatic shut-off after about 15 minutes of inactivity, buzzer alerts and Data Hold. The title describes auto-ranging. The specification lines show a 2-year warranty and cite UL 61010-1 and IEC 61010-2-030.

Limits from the listing: The listing does not state a CAT rating, and it does not list a current range. For a related look at auto-ranging meters, see the auto-ranging digital multimeter roundup.

Skip if: the circuit is a wall outlet, a panel or service wiring, because the listing gives no CAT rating to match against.

Pick 4: FNIRSI DMC-100

Best for: a clamp meter that recharges over Type-C and reads current without breaking the circuit.

Strengths from the listing: AC and DC current up to 600A, True RMS, a 2-inch TFT display with 10 brightness levels and a dark and light theme. The listing says the meter stores 8 sets of real-time data and 30 sets of historical records, and that it also covers voltage, resistance, capacitance, frequency, temperature, non-contact voltage, continuity and diode checks. It has a 1500mAh lithium battery with Type-C charging and lists UL 61010-1, CE and RoHS.

Limits from the listing: The listing does not state a CAT rating or a warranty. The title gives 9999 counts, while one bullet gives 10000. The listing says voltage must be measured with the test leads and that the clamp jaws are for current measurement only. It does not state the smallest DC current the clamp reads, or which sensing method the clamp uses.

Fluke’s page on Hall-effect clamp meters says that type can measure both AC and DC current up to the kilohertz range, about 1000 Hz. That page does not describe this model, so it cannot confirm this clamp’s DC range. For a wider look at true RMS clamp meters, see the true RMS clamp meter roundup.

Skip if: you need voltage from the clamp jaws, or you need a stated low-current DC floor.

Pick 5: Klein ET920

Best for: checking what a USB charger, cable or power bank delivers to a device.

Strengths from the listing: The listing gives voltage from 3 to 20V DC, current from 0.05 to 3A on USB-A and 0.05 to 5A on USB-C, and continuous monitoring for up to 1000 hours. It also reports capacity, energy and calculated resistance, stores 10 readings and detects overload. The bullets claim Qualcomm Quick Charge compatibility and a 6.6 ft drop rating. The specification lines show a 1-year manufacturer warranty.

Limits from the listing: This is a USB tester, not a multimeter for wiring. The listing does not state a CAT rating, and it does not describe a rechargeable battery.

Skip if: you need to measure a wall outlet, a breaker or a motor circuit.

Pick 6: YOJOCK

Best for: a USB tester that reads voltage, current, capacity and power on a device’s USB line.

Strengths from the listing: The ranges are 3.6 to 32.0V for voltage, 0 to 8.0A for current, 0 to 99999mAh for capacity and 0 to 256W for power. The listing names USB D+ and D- voltage readings, eight display screens and support for PD3.0, PD2.0, QC3.0, QC2.0 and BC1.2. The bullets describe over-voltage and over-current protection and a data save on sudden power loss.

Limits from the listing: The listing does not state a CAT rating or a rechargeable battery. For warranty questions, it directs buyers to the seller.

Skip if: you need a meter for a mains circuit or a meter you can charge over USB-C itself.

Pick 7: YEREADW

Best for: a USB-C tester with the highest current figure among the USB testers in this pool, 0 to 12A.

Strengths from the listing: The listing gives voltage from 4V to 30V, current from 0 to 12A on a 12A terminal, and an accuracy figure of plus or minus 1 percent plus 5 counts. It names PD2.0 and PD3.0, QC2.0 and QC3.0, FCP, SCP, AFC, PE, DASH, VOOC and Super VOOC protocols. The curve function offers 5-minute, 15-minute, 60-minute and 2-hour settings, and the display shows voltage, current, power, capacity, energy, time and CPU temperature.

It describes USB and Type-C power for the tester, not a rechargeable battery.

Skip if: you need a meter that charges itself over USB-C, or any meter for a mains circuit.

How we chose

The pool for this query held twelve listings, checked on 24 October 2026 from the scanned research record. A listing stayed in the list if it named a USB-C or Type-C charging port for the meter itself, or a USB measurement function, and if it gave at least one measurement range or count. Seven listings passed that test. The list is not ranked, and no listing was preferred for its price or ratings, because the research record holds neither.

Five listings did not pass both checks. The Neoteck voltage pen runs on AAA batteries and its listing names no USB charging. The DuHeSin inline adapter gives a 20-volt input and a 240W figure, but no measurement range. The FNIRSI LCR-P1 has a USB-C charging port, but its listing describes transistor and LCR tests, not voltage or current ranges. The CapMaster 470F is a capacitance tester on AA batteries or micro USB power, with no voltage or current figures. The AVHzY CT-3 is the exception among the five: it has a range of 0 to 26V and 0 to 6A, but it was left out to keep the table to seven rows, because its bullets focus on PC software and Lua scripting rather than on a meter’s USB charging or its use on a USB line.

Mistakes to avoid

• Reading a USB-C port as a CAT rating. The port charges the battery. The CAT rating decides which circuits the meter may test.
• Picking a USB tester for a wall outlet or a breaker. The USB testers here state USB ranges only.
• Assuming a listed count is the same across listings. The FNIRSI DMC-100 title and a bullet disagree on the count.
• Charging a damaged rechargeable meter. Inspect the battery and the cable first.
• Trusting an accessory count without checking the contents. The FS899L kit title and its specification lines do not agree.

What we could not verify

• The sources opened for this guide do not cover the CAT rating of any meter in the picks. The listings for the NJTY T3, the FNIRSI DMC-100 and the USB testers state none.
• The FS899L 20-piece kit: the title and bullets describe 20 pieces, while the specification lines name only an instruction manual. The listing does not settle which is correct.
• The FNIRSI DMC-100 count: the title gives 9999 and one bullet gives 10000. The listing does not say which is the rated count.
• Battery life and charge time. The listings give a 2-hour charge and up to 8 hours of use for the FS899L, but the sources opened here do not cover battery life or charge time for any meter.
• Warranty terms for the FS899L listings and the FNIRSI DMC-100 are not stated. The Klein ET920 lists 1 year, and the NJTY T3 lists 2 years.
• How any of these meters performs in use. The sources opened here do not compare these models with each other.

FAQ

Does a USB-C port mean the meter can measure a USB charger?

No. In the FS899L, NJTY T3 and DMC-100 listings, the USB-C or Type-C port is for charging the meter’s own battery. The Klein ET920 and the YOJOCK are USB testers built to read a USB line, and their listings describe that job. Check the measurement list on the listing before you assume a meter can read USB output.

Which meters in this pool state a CAT rating?

The two FS899L listings state CAT III 1000V and CAT IV 600V. The Neoteck voltage pen names a CAT III 600V rating in one bullet, but it runs on AAA batteries and its listing names no USB charging. The other listings say nothing about a CAT rating.

Can I charge the meter from a power bank or a laptop port?

The listings name a USB-C or Type-C charging port, but they do not name a charger, a power bank or a wattage for charging. The sources opened for this guide do not cover that either, so check the meter’s manual before you connect it to anything other than the charger it came with.

Is a lithium battery in a meter a fire risk?

The Western Michigan University guidance says to inspect batteries for damage before use and to dispose of damaged ones promptly. It warns against burning, disassembling or puncturing batteries. The guidance is written for lithium-ion cells, and the listings here do not say which cell type each meter uses.

Can a clamp meter measure DC current?

The FNIRSI DMC-100 listing states AC and DC current up to 600A. Fluke says Hall-effect clamp meters can measure both AC and DC current up to about 1000 Hz. The DMC-100 listing does not say which sensing method it uses, so the Fluke page does not confirm its DC range.

Which should I choose for work on wiring?

Of the four multimeters and clamp meters that recharge over USB-C, the two FS899L listings are the only ones that state a CAT rating. Choose one only when that rating suits the circuit.

Bottom line

Use the USB-C charging as a convenience, and treat the CAT rating as the deciding figure. A meter is a match for a circuit only when its listing states a CAT rating that suits that circuit.

Sources

• https://www.fluke.com/en-us/learn/blog/electrical
• https://www.fluke.com/en-us/learn/blog/digital-multimeters/testing-your-test-leads
• https://www.fluke.com/en-us/learn/blog/clamps/inside-hall-effect-clamp-meters
• https://wmich.edu/ehs/lithium-ion-battery-safety-guidance
• https://www.law.cornell.edu/cfr/text/29/1910.333