Best Serial Adapters (2026 Guide)

We selected top-rated serial adapters by average user rating and review volume, emphasizing FTDI chipset presence and a variety of connector types (USB-to-serial, DB9, DB15, multiport) to represent common use cases

This roundup covers well-reviewed serial adapters and breakout connectors for interfacing RS-232 and D-sub devices with modern USB hosts and development setups. Picks were chosen based on aggregated user ratings, review volume, common chipset compatibility (FTDI), and the range of connector types (DB9, DB15, multiport) relevant to hobbyist and professional use

Top Picks

  1. 1
    USB to RS232 adapter with FTDI chipset

    USB to RS232 adapter with FTDI chipset

    StarTech • ★ 4.1/5 • Mid-Range

    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
    Check current price on Amazon →
  2. 2
    DB9 Male Breakout Connector with Case

    DB9 Male Breakout Connector with Case

    ANMBEST • ★ 4.0/5 • Budget

    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
    Check current price on Amazon →
  3. 3
  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

    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
  6. 6
  7. 7
  8. 8
  9. 9
  10. 10

Buying Guide

Confirm interface and connector type

Match the adapter to the serial interface you need—USB-to-RS232 for PC-to-serial conversion or DB9/DB15 breakout connectors for direct D-sub wiring and pin access

Check chipset compatibility

Adapters using FTDI chipsets typically offer broad OS driver support and stable serial communication, which matters for cross-platform reliability

Choose single vs multiport by workflow

Select a 4-port USB-to-RS232 unit if you need multiple simultaneous serial connections; single-port adapters are simpler for one-off device access

Consider breakout features and cases

Solderless DB9/DB15 breakout boards and connectors with cases simplify wiring, provide strain relief, and help organize signal labeling during prototyping or testing

Prioritize reviews and rating consistency

Look for adapters with high average ratings and substantial review volume—these indicate fewer compatibility issues and more reliable performance in varied setups