AdapterGuru
Know before you plug in
INTERACTIVE PLUG IDENTIFIER

DC Barrel Connector Finder

DC power plugs look identical at a glance, but millimeter differences in Outer Diameter (OD) and Inner Pin Diameter (ID) cause loose connections, sparking, or physical fit failures.

Filter Dimensions

The #1 Sizing Trap: 5.5×2.1 vs 5.5×2.5mm

Both plugs have identical 5.5mm outer shells. A 2.5mm plug inserted into a 2.1mm jack will feel loose and lose connection if bumped. Always verify inner pin diameter with calipers or device specs!

Selected Plug Dimension
5.5 × 2.1 mm

Standard DC plug used on 90% of routers, CCTV, and LED strips.

ODID
5.5 mm × 2.1 mmHigh Popularity
Common (Non-EIAJ)

Typical Uses: Wi-Fi Routers, Cable Modems, CCTV Cameras, LED Strips (12V), Arduino UNO/Mega, Desktop Monitors

Brands: TP-Link, Netgear, Asus, Hikvision, Dahua, AnkerTypically 5V, 9V, 12V, or 24V DC
5.5 mm × 2.5 mmHigh Popularity
Common (Non-EIAJ)

Typical Uses: Toshiba/Asus Laptops, High-Wattage Routers, Digital Audio Amplifiers, 3D Printers, 24V LED Drivers

Brands: Toshiba, Asus, Lenovo (older), Lepy/SMSL AudioTypically 12V, 19V, 24V DC (higher current >3A)
3.5 mm × 1.35 mmHigh Popularity
EIAJ-02 (RC-5320A)

Typical Uses: Powered USB Hubs, 5V Mini Desk Fans, IP Security Cameras, Android TV Boxes, External Enclosures

Brands: Anker, TP-Link Tapo, Ugreen, SabrentStandard 5V (3.15V to 6.3V EIAJ-02)
4.0 mm × 1.7 mmHigh Popularity
EIAJ-03 (RC-5320A)

Typical Uses: Sony PSP (1000/2000/3000), Lenovo Ideapad Ultrabooks, Echo Dot (Gen 2/3/4), Small LED Projectors

Brands: Sony, Lenovo, Amazon, Xiaomi5V (PSP), 12V (Echo Dot), 20V (Lenovo IdeaPad)
4.8 mm × 1.7 mm
Bullet Tip (Proprietary)

Typical Uses: HP Compaq Laptops, Asus Netbooks, LG Monitors, Certain POS Terminals

Brands: HP, Compaq, Asus (Eee PC)Typically 18.5V or 19V DC
3.0 mm × 1.1 mm
Micro DC

Typical Uses: Acer Aspire / Swift, Asus ZenBook, Samsung Chromebooks, Slim Tablets

Brands: Acer, Asus, SamsungTypically 19V DC (45W/65W)
2.5 mm × 0.7 mm
EIAJ-01 (RC-5320A)

Typical Uses: Digital Photo Frames, Mini Android Tablets, Bluetooth Receivers, GPS units

Brands: Generic 5V micro gadgetsStrictly 5V DC (0V to 3.15V EIAJ-01)
4.5 mm × 3.0 mmHigh PopularityCenter Smart Pin
Smart Tip with Center Pin

Typical Uses: HP Envy/Spectre/Pavilion (Blue Tip), Dell XPS/Inspiron/Latitude (Small Barrel)

Brands: HP, Dell19.5V DC (45W, 65W, 90W)
7.4 mm × 5.0 mmHigh PopularityCenter Smart Pin
Large Barrel with Center Pin

Typical Uses: Dell Precision/Alienware/Latitude, HP EliteBook/ZBook, Docking Stations

Brands: Dell, HP19.5V DC (65W up to 240W)
6.5 mm × 4.4 mmCenter Smart Pin
EIAJ-05 (RC-5320A)

Typical Uses: Sony VAIO Laptops, LG & Sony Desktop Monitors, Sony Audio Receivers

Brands: Sony, LG, Fujitsu19.5V DC (Sony) or 19V DC (LG)

How to Accurately Measure a DC Barrel Plug

Step 1: Outer Diameter (OD)

Use the large external jaws of a digital caliper across the outside of the metal barrel cylinder.

Step 2: Inner Diameter (ID)

Use the smaller top internal jaws inside the hollow opening, or insert a known 2.1mm vs 2.5mm gauge pin.

Step 3: Barrel Length

Standard depth is 9.5mm to 10.0mm. Plugs shorter than 9mm may fail to reach the internal contact.

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