Best Serial Adapters (2026 Guide)

• 10 products compared from 7 brands • avg ItemOracle score 3.9/5

We selected products based on aggregate star rating, review volume, chipset or feature set (FTDI, multibus, breakout), connector types, and suitability for hobbyist or industrial use

The Verdict

Top Picks

  1. 1
    USB to RS232 adapter with FTDI chipset

    Best Overall USB to RS232 adapter with FTDI chipset

    StarTech • ★ 4.1/5 • Mid-Range

    Best for cross-platform USB-to-RS232 use: FTDI chipset for stable driver support and DB9 serial connectivity

    USB to serial RS232 adapter converting USB to a null modem DB9 port. Compatible with Windows, Mac, and Linux. Customers praise plug-and-play setup and reliable FTDI FT232R chip

    • FTDI-based reliability
    • USB to RS232 null modem capability
    • cross-platform compatibility
    Buy at Amazon →
  2. 2
    DB9 breakout connector set (5 male + 5 female) with case

    Best Value DB9 breakout connector set (5 male + 5 female) with case

    ANMBEST • ★ 4.0/5 • Budget

    Best for prototyping: five male and five female DB9 breakout connectors in a protective case for flexible wiring

    DB9 breakout boards for RS232 serial connections with solderless terminals and durable casing. Easy to wire and assemble; customers note good quality and functionality

    • solderless DB9 terminals
    • case-protected breakout
    • mixed-quality but functional reviews
    Buy at Amazon →
  3. 3
    DB9 Male Breakout Connector with Case

    DB9 Male Breakout Connector with Case

    ANMBEST • ★ 4.0/5 • Budget

    Best single breakout solution: a DB9 male solderless connector in a compact case for quick custom wiring

    DB9 solderless breakout board for RS232 serial connections. Provides easy wiring and durable joints for reliable signal transfer. Customers note solid quality and ease of use, though some find it bulky

    • solderless terminal adapter
    • case with long bolts
    • pure copper plated joints
    Buy at Amazon →
  4. 4
    Gearmo 4 Port USB to RS232 Adapter with FTDI

    Gearmo 4 Port USB to RS232 Adapter with FTDI

    Gearmo • ★ 3.9/5 • Mid-Range

    Best for multi-device setups: four-port USB-to-RS232 adapter with FTDI chipset for stable multi-serial connectivity

    USB to RS-232 adapter with four ports and FTDI chipset for cross-platform use. Plug-and-play with COM port retention for stable serial connections. Customers note reliable Linux compatibility and solid build quality

    • multiplatform compatibility
    • four COM ports
    • no external power required
    Check current price on Amazon →
  5. 5
    DB15 Solderless Connector 15-pin Breakout Board with Case

    DB15 Solderless Connector 15-pin Breakout Board with Case

    ANMBEST • ★ 3.9/5 • Mid-Range

    Best for larger D-sub pinouts: DB15 solderless breakout board with case for easy access to all 15 pins

    Solderless DB15 breakout board for RS232 D-SUB ports, with a durable copper joint and protective PP casing. Customers note ease of use and reliable functionality

    • durable solder joints
    • easy-to-use breakout
    • protective outer case
    Check current price on Amazon →
  6. 6
    DB9 Female Breakout Connector 10-pack

    DB9 Female Breakout Connector 10-pack

    ANMBEST • ★ 3.9/5 • Budget

    pack for repairs: ten DB9 female solderless breakouts that simplify replacing or wiring serial ports

    DB9 female breakout board for solderless RS232 connections with case. Helps wire and build serial cables; users report good quality and ease of use

    • solderless RS232 breakout
    • durable outer casing
    • easy wiring
    Check current price on Amazon →
  7. 7
    4 Port USB to RS232 DB9 Serial Adapter Cable (5ft) ELECABLE

    4 Port USB to RS232 DB9 Serial Adapter Cable (5ft) ELECABLE

    ELECABLE • ★ 3.8/5 • Budget

    Best cable-style multiport: four-port USB-to-RS232 DB9 cable that keeps multiple serial devices connected without hubs

    USB to RS-232 adapter supporting 4 ports, compatible with MAC, Windows, Android, Linux. Provides remote wake up and power management; suitable for GPS, modems, printers, scanners, cameras. Customer note: reliable performance and good cable quality

    • 4-port RS-232 support
    • USB to RS-232 conversion
    • remote wake up and power management
    Check current price on Amazon →
  8. 8
    USB/RS232/TLL to RS232/485/TLL Multibus Converter

    USB/RS232/TLL to RS232/485/TLL Multibus Converter

    waveshare • ★ 3.8/5 • Budget

    Best for mixed-level conversion: multibus USB/RS232/TLL adapter offering RS232, RS485 and TTL interfaces with industrial options

    Industrial isolated converter supporting USB, RS232, TTL to RS232, 485, TTL with onboard power isolation and protection circuits. Built on FT232RL for reliable USB communication

    • multibus isolated converter
    • USB/RS232/TTL to RS232/485/TLL
    • onboard isolation and protection
    Check current price on Amazon →
  9. 9
    DB9 Solderless Breakout Connector 3Male+3Female 9-pin

    DB9 Solderless Breakout Connector 3Male+3Female 9-pin

    Dbilida • ★ 3.8/5 • Budget

    Best small breakout kit: three male and three female DB9 solderless connectors for compact serial wiring tasks

    DB9 solderless breakout with labeled ports for quick wiring. Copper joints and 24K gold-plated connector enhance connectivity and durability. 16mm thin case for flexible wiring

    • clear port labeling on both sides
    • durable copper joints with gold plating
    • lead-free RoHS compliant
    Check current price on Amazon →
  10. 10
    DR302 DIN Rail Modbus Gateway: RTU to TCP RS485 to Ethernet

    DR302 DIN Rail Modbus Gateway: RTU to TCP RS485 to Ethernet

    PUSR • ★ 3.6/5 • Mid-Range

    Best for industrial networking: DIN-rail Modbus gateway converting RTU/RS485 to TCP for integrating serial devices on Ethernet

    Modbus gateway converting RTU to TCP/UDP with RS485 to Ethernet. Compact, lightweight, simple configuration. Customer insight hints at ease of use

    • Modbus RTU to Modbus TCP conversion
    • DIN rail mounted gateway
    • multi-protocol server/client support
    Check current price on Amazon →

Buying Guide

Choose the right interface

Confirm whether you need USB-to-RS232, RS232-to-TTL, RS485, or Ethernet/Modbus conversion before buying to avoid incompatibility

Check chipset compatibility

FTDI-based adapters are widely supported across OSes and reduce driver issues compared with generic chipsets

Decide on port count and form factor

Single-port cables suit occasional use while 4-port adapters or DIN-rail gateways work better for multiple devices or industrial installations

Pick the correct connector style

DB9 and DB15 solderless or breakout boards let you wire custom signals, while molded DB9 cables provide a fixed, ready-to-plug solution

Consider isolation and industrial features

Choose converters with isolation or RS485 support for noisy environments and longer field runs to protect devices and improve reliability