For legacy hardware, DB9 to DB25 adapters remain a practical solution to connect 9-pin devices to 25-pin ports. This guide highlights top options designed for reliable serial communication, shielding from interference, and easy installation. The selections cover straight-through adapters and cross-wired/nul-modem cables to fit a range of setups, from older PCs to industrial equipment. Each entry summarizes compatibility, form factor, and notable features to help compare performance and choose the best fit for your needs.
| Product | Brand | Connector Type | Notes |
|---|---|---|---|
| DB9 Female to DB25 Male Serial Adapter | StarTech.com | DB9 F to DB25 M | Straight serial adapter for quick port connections |
| DB9 Male to DB25 Female Serial Adapter | StarTech.com | DB9 M to DB25 F | Balanced compatibility for various devices |
| 10 ft Cross Wired DB9 to DB25 Null Modem Cable | STARTECH.COM | DB9 F to DB25 M, cross-wired | Null modem capability for PC-to-PC or device bridging |
| DB9 Female to DB25 Male Adapter (2-Pack) | ECSiNG | DB9 F to DB25 M | Shielded, suitable for multiple devices |
| DB9 Female to DB25 Male Low-Profile Adapter | Cable Leader | DB9 F to DB25 M | Low-profile, space-saving design |
StarTech.com DB9 to DB25 Serial Adapter – F/M
The StarTech AT925FM is a DB9 female to DB25 male serial adapter, designed to connect a 9-pin serial device to a 25-pin port. It features a robust construction with molded connectors suitable for longer life. This straight-through adapter is ideal for applications requiring simple, direct mapping between DB9 and DB25 connectors in a compact form factor.
- Connector: DB9 Female to DB25 Male
- Type: Serial adapter
- Use case: Direct DB9 to DB25 connections
StarTech.com DB9 to DB25 Serial Adapter – M/F
The StarTech AT925MF offers a DB9 male to DB25 female configuration, enabling flexible coupling between common serial devices. It’s a compact, easy-to-install adapter suitable for lab benches, industrial control panels, and legacy equipment where port mapping is required.
- Connector: DB9 Male to DB25 Female
- Type: Serial adapter
- Use case: Flexible DB9/DB25 pairing
STARTECH.COM 10 ft Cross Wired DB9 to DB25 Null Modem Cable
The SCNM925FM 10ft cross-wired cable functions as a null modem cable, pairing a DB9 female with a DB25 male connector. This enables direct PC-to-PC file transfers or serial connections between devices without a modem in the middle. It emphasizes quality and durability with molded connectors and EMI shielding.
- Type: Cross-wired serial cable, null modem
- Length: 10 ft
- Compatibility: DB9F to DB25M
ECSiNG 2Pcs DB9 Female to DB25 Male Serial Adapters
These ECSiNG adapters provide a shielded, barrier-free design to securely connect DB9 female devices to DB25 male ports. They are built with metal and plastic materials to offer a long service life and resistance to external EMI/RFI interference, suitable for devices requiring stable serial communication in demanding environments.
- Quantity: 2 pieces
- Connector: DB9 Female to DB25 Male
- Shielding: EMI/RFI protection
Cable Leader DB9 Female to DB25 Male Low Profile Adapter
The Cable Leader low-profile adapter offers a space-saving solution ideal for tight spaces and compact installations. It includes EMI shielding to protect data integrity and complies with RoHS for environmental safety, making it suitable for both professional and home setups where space is at a premium.
- Design: Low-profile, space-saving
- Shielding: EMI protection
- Compliance: RoHS
PNGKNYOCN 4.5 Feet DB9 to DB25 Serial Cable
This 4.5-foot DB9 (Female) to DB25 (Male) cable merges a 9-pin port with a 25-pin port, enabling direct printer or serial device connections. The nickel-plated connectors and high-quality PVC housing enhance durability, wear resistance, and smooth transmission, making it suitable for regular use in office and industrial environments.
- Length: 4.5 ft
- Connectors: DB9 Female to DB25 Male
- Construction: Nickel-plated connectors, PVC housing
STARTECH.COM 10 ft Cross Wired DB9 to DB25 Serial Null Modem Cable (Pack of 2)
The per-pack description covers dual 10-foot cross-wired cables with DB9 female to DB25 male connectors, designed for null modem applications. The cables are built to offer reliable connections with molded connectors and shielding to minimize EMI, making them suitable for PC-to-PC or device-to-device serial communications.
- Quantity: Pack of 2
- Length: 10 ft each
- Function: Null modem, cross-wired
LEMENG DB9 Male to DB25 Female Mini Serial Port Cable Adapter
The LEMENG adapter provides a cost-effective solution for converting a 9-pin serial port to a 25-pin port. It is easy to install and uses a basic 1 x DB9 Male to 1 x DB25 Female configuration, suitable for quick field replacements and maintenance tasks.
- Configuration: 1 DB9 Male to 1 DB25 Female
- Use: Quick conversion and compatibility
- Material: Durable construction
Buying Guide: Key Considerations For DB9 To DB25 Adapters
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<liConnector type and wiring: Decide between straight-through adapters (DB9F to DB25M or DB9M to DB25F) and cross-wired/Null Modem cables. Cross-wired variants enable direct PC-to-PC connections and data transfer between two devices that use the same data terminal equipment (DTE) or data communication equipment (DCE) conventions.
<liShielding and EMI/RFI immunity: Look for adapters and cables with molded connectors and EMI shielding to protect signals in environments with potential interference, especially industrial settings or long cable runs.
<liLength and space constraints: Choose cable lengths that fit your setup. Low-profile adapters are beneficial in tight spaces, while longer cables provide flexibility for distant devices.
<liDurability and build quality: Molded connectors, nickel-plated conductors, and robust housings extend service life and reduce wear from repeated mating cycles and field use.
<liCompatibility: Verify the port types on both devices (DB9 vs. DB25, male vs. female) and ensure the adapter supports the intended combination without adapters in between.
<liEnvironmental standards: For professional installations, consider RoHS compliance and any industry standards relevant to your equipment environment.
<liCost and quantity: If you need multiple connections, evaluate multi-pack options and overall cost per connection, weighed against reliability and warranty considerations.
<liApplication context: Separate choices are better for straight-through serial tasks (modems, printers, equipment with DB25 ports) versus PC-to-PC file transfers (null modem cables).