JST XH Connector: Complete Guide & FAQ

What Is a JST XH Connector?

The JST XH connector is a 2.5mm pitch wire-to-board connector manufactured by Japan Solderless Terminals (JST), a Japanese company founded in 1957 and recognized globally as the industry standard for miniature electrical connectors.

The "XH" designation refers to the connector's housing style within JST's product lineup. Its 2.5mm pitch places it in the mid-range of JST's series — larger than the SH (1.0mm), GH (1.25mm), ZH (1.5mm), and PH (2.0mm) series, making it easier to handle while still maintaining a compact footprint suitable for space-constrained PCB designs.

JST XH connectors are found in millions of consumer electronics, RC hobby products, 3D printers, and industrial devices worldwide. If you have ever charged a LiPo battery pack, you have almost certainly used a JST XH connector. Browse our full range of JST XH 2.5mm Connectors including housings, contacts, and PCB receptacles.

JST XH Connector Specifications

Specification	Value
Pitch	2.5mm
Current Rating	3A per contact
Voltage Rating	250V AC/DC
Wire Gauge	AWG 22–30
Contact Material	Brass (tin or gold plated)
Housing Material	PA66 (Nylon), UL94V-0 rated
Operating Temperature	-25°C to +85°C
Pin Count	2 to 20 pins
Mating Cycles	30 minimum (rated)
Contact Resistance	20mΩ max
Insulation Resistance	1000MΩ min
Withstanding Voltage	1000V AC/1 minute

JST XH vs All JST Series: Complete Comparison

Understanding where XH fits within the full JST lineup is essential for selecting the right connector. Here is a comprehensive comparison of all major JST series:

Series	Pitch	Current	Voltage	Wire AWG	Pin Count	Configuration	Typical Use
SH	1.0mm	1A	50V	32–28	2–20	Wire-to-Board	Wearables, compact sensors
GH	1.25mm	1A	50V	30–26	2–15	Wire-to-Board	FPV drones, flight controllers
ZH	1.5mm	1A	50V	32–26	2–13	Wire-to-Board	Compact PCB connections
PH	2.0mm	2A	100V	32–24	2–16	Wire-to-Board	RC batteries, Arduino shields
XH	2.5mm	3A	250V	30–22	2–20	Wire-to-Board	LiPo balance leads, DIY electronics
SM	2.5mm	3A	250V	28–22	2–18	Wire-to-Wire	Automotive, appliances
EH	2.5mm	3A	250V	32–22	2–15	Wire-to-Board	Industrial equipment
RCY	2.5mm	3A	250V	28–22	2	Wire-to-Wire	RC cars, battery packs

Key distinction: XH, SM, EH, and RCY all share a 2.5mm pitch but are not interchangeable. Their housing geometries, locking tab designs, and contact configurations differ. Always verify the exact series before ordering. Need both PH and XH? See our JST PH & XH Connector collection.

How to Identify a JST XH Connector: Step-by-Step Guide

Misidentifying a JST connector is one of the most common and costly mistakes in electronics sourcing. Follow these five steps to identify an XH connector with confidence.

Step 1: Determine the Connection Type

First, establish what the connector is doing:

• Wire-to-Board: One side connects to a PCB (through-hole or SMD receptacle), the other to a wire harness. XH is a wire-to-board series.
• Wire-to-Wire: Both sides connect wires. If you see this, it is likely SM or RCY, not XH.

If your connector has a PCB-mounted receptacle with a wire plug, proceed to Step 2.

Step 2: Measure the Pitch

Pitch is the most reliable identifier. Use a digital caliper to measure the center-to-center distance between two adjacent pins.

• XH pitch = 2.5mm exactly
• 2.54mm (0.1 inch) = DuPont / standard header — NOT JST XH
• 2.0mm = JST PH
• 1.25mm = JST GH

Pro tip: 2.5mm and 2.54mm look nearly identical to the naked eye. Always use a caliper — never estimate by sight. A 0.04mm difference means the connectors will not mate reliably.

Step 3: Count the Number of Positions (Pins)

Count the total number of pins or slots in the housing. JST XH is available in 2 through 20 positions. For LiPo balance applications specifically:

• 2S battery = 3-pin XH balance lead
• 3S battery = 4-pin XH balance lead
• 4S battery = 5-pin XH balance lead
• 5S battery = 6-pin XH balance lead
• 6S battery = 7-pin XH balance lead

Step 4: Examine Physical Characteristics

Look for these XH-specific visual traits:

• Housing color: Typically white or natural (off-white). Color alone is not definitive as aftermarket versions vary.
• Locking tab: XH has a friction latch on the top of the plug housing. It requires pressing down while pulling to release.
• Single row: XH is always single-row. Dual-row at 2.5mm pitch indicates SM series.
• Through-hole or SMD receptacle: XH receptacles are available in both through-hole and SMD configurations.

Step 5: Check for Markings or Part Numbers

Examine the housing surface under magnification:

• Look for molded text such as "XH", "JST", or a part number beginning with "B" (receptacle) or "XHP" (plug housing)
• Common part numbers: XHP-2 (2-pin plug), XHP-3 (3-pin plug), B2B-XH-A (2-pin receptacle)
• Cross-reference with JST's official datasheet library at jst.com for confirmation

JST XH Connector Pinout

JST XH connectors follow a standardized pin numbering convention that is consistent across all pin counts:

• Pin 1 is located on the left side when the locking tab faces upward
• Pin numbering increases sequentially from left to right
• The polarization key physically prevents reverse insertion
• For battery balance leads: Pin 1 = most negative cell reference, last pin = most positive
• For power applications: always verify polarity with a multimeter before first connection

Warning: Never assume polarity based on wire color alone. Always verify with a multimeter before connecting to sensitive electronics.

How to Crimp JST XH Connectors: Complete Process

Tools Required

• JST XH crimping tool (Engineer PA-09, PA-21, or IWISS SN-01BM recommended)
• Wire stripper (set to AWG 22–28 range)
• Digital multimeter
• Magnifying glass or loupe (optional but recommended)

Prefer ready-to-use solutions? Our JST XH pre-crimped cable assemblies come with contacts already crimped and inserted — no tools required.

Wire Preparation

• Strip 2.0–2.5mm of insulation — no more, no less
• Do not tin (solder) the wire end before crimping — this creates a brittle joint
• Ensure no stray wire strands extend beyond the conductor barrel

Crimping Process

1. Select the correct die: Use the AWG-appropriate slot on your crimping tool
2. Position the contact: Place the XH crimp contact in the tool with the wire barrel facing up
3. Insert the wire: Slide the stripped wire end into the contact so the conductor sits in the wire barrel and insulation sits in the insulation barrel
4. Crimp: Squeeze the tool handles fully until the ratchet releases
5. Inspect: The wire barrel should be fully compressed around the conductor; the insulation barrel should grip the insulation jacket
6. Pull test: Tug the wire firmly — it should not pull out with hand force
7. Insert into housing: Push the crimped contact into the XH housing from the rear until you hear and feel a click
8. Verify: Gently tug the wire from the front — the contact should not back out

Common Applications of JST XH Connectors

• RC hobby — LiPo balance leads: The most widespread XH application. Every major LiPo battery manufacturer uses XH for balance charging leads.
• 3D printers: Thermistor connections, fan headers, and filament runout sensors on Creality, Prusa, and Bambu Lab printers commonly use XH.
• Arduino and Raspberry Pi projects: XH's 3A rating and easy hand-termination make it popular for DIY power connections.
• LED drivers and lighting: Connecting LED strips to constant-current drivers in commercial lighting fixtures.
• Solar energy systems: Small-scale solar charge controller connections and battery monitoring leads.
• Robotics and education: Servo power leads and sensor connections in STEM robotics kits.
• Industrial equipment: Panel wiring and sensor connections where a secure, polarized connection is required.

Tips and Tricks for Accurate Identification

• Always use a caliper, never estimate: 2.5mm and 2.54mm are visually indistinguishable. A caliper is the only reliable tool.
• Do not assume brand from appearance: Many manufacturers produce XH-compatible housings. Verify with markings or datasheets.
• Check the datasheet: JST publishes free datasheets for every series at jst.com. A part number search takes 30 seconds and eliminates guesswork.
• Beware of counterfeits: Low-quality XH clones may have slightly different housing dimensions that cause poor mating. Source from reputable suppliers.
• Use a magnifying glass for markings: XH housing text is often 0.5mm tall — a 10x loupe makes reading part numbers straightforward.
• Test with a known-good mating connector: If you have a confirmed XH receptacle, test-fit the unknown plug. Correct mating requires zero force and a positive click.

JST XH Connector FAQ

Are JST XH connectors polarized?

Yes. JST XH connectors feature a polarization key molded into the housing that physically prevents incorrect insertion. The plug can only mate with the receptacle in one orientation, eliminating reverse-connection errors.

What wire gauge should I use with JST XH connectors?

JST XH connectors are rated for AWG 22 to AWG 30. For applications near the 3A maximum, use AWG 22 or AWG 24. For signal or low-current applications, AWG 26–28 is sufficient and easier to route in tight spaces.

Can I use JST XH connectors for LiPo battery balance leads?

Yes — JST XH is the industry-standard connector for LiPo balance leads. 2S packs use 3-pin XH, 3S use 4-pin, 4S use 5-pin, and so on. Most balance chargers include XH-compatible balance ports.

What is the difference between JST XH male and female?

The plug (female contacts, wire side) has crimp contacts recessed inside the housing and attaches to the wire harness. The receptacle (male pins, board side) is PCB-mounted with through-hole or SMD pins. In ordering, specify "plug" for the wire side and "receptacle" for the PCB side.

Are JST XH connectors compatible with other 2.5mm pitch connectors?

No. Despite sharing a 2.5mm pitch with SM, EH, and RCY series, JST XH connectors are only compatible with other XH series connectors. Housing geometry, locking tab position, and contact design differ between series, preventing reliable cross-series mating.

How many amps can a JST XH connector handle?

JST rates XH at 3A per contact. For continuous-duty applications, derate to 80% (2.4A per contact). Total connector current capacity depends on the number of current-carrying contacts and ambient temperature. Never exceed the rated current — overloading causes contact heating, insulation damage, and potential fire risk.

Can JST XH connectors be disconnected and reconnected repeatedly?

Yes. JST rates XH for a minimum of 30 mating cycles. In practice, carefully handled connectors typically last significantly longer. Avoid pulling on the wire rather than the housing, as this stresses the crimp joint and reduces connector lifespan.

What is the difference between JST XH and DuPont connectors?

This is one of the most common points of confusion. DuPont-style connectors use a 2.54mm pitch (0.1 inch), while JST XH uses 2.5mm. They look nearly identical but are not interchangeable. DuPont connectors are common on Arduino headers and breadboard jumper wires. JST XH connectors have a more secure locking mechanism and higher current rating.

Where can I find JST XH datasheets?

Official JST datasheets are available free at jst.com. Search by series name "XH" or by part number. Datasheets include full dimensional drawings, material specifications, and electrical ratings.

Summary

The JST XH connector is the workhorse of the 2.5mm pitch connector world — reliable, widely available, and suitable for a broad range of applications from RC hobby to industrial wiring. Its 3A current rating, polarized housing, and broad pin count range make it one of the most versatile connectors in the JST lineup.

When identifying an XH connector, always measure pitch with a caliper, verify the single-row wire-to-board configuration, and check for XH markings on the housing. When in doubt, cross-reference with JST's official datasheet.

Ready to source JST XH connectors for your project? Shop our complete range below:

• JST XH 2.5mm Connectors — housings, contacts, and PCB receptacles
• JST XH Cables — pre-crimped wire assemblies, ready to use
• JST Connector Kits — assorted connectors for prototyping and repair