Best Function Generators (2026 Guide)

We ranked products by aggregated user rating and review volume while ensuring coverage of key features (current/voltage outputs, DDS/arbitrary waveform, channel count) relevant to industrial and lab applications

This guide covers top-rated function and signal generators for tools and industrial use, emphasizing units useful for PLC testing, lab-bench work, and signal simulation. Picks were chosen based on aggregated user ratings and review volume, with attention to feature set (4–20mA, 0–12V/0–10V outputs, DDS/arbitrary waveform, dual-channel) and real-world utility

Top Picks

  1. 1
    DROK 4-20mA/0-10V Dual Signal Generator (2 pcs)

    DROK 4-20mA/0-10V Dual Signal Generator (2 pcs)

    DROK • ★ 3.9/5 • Mid-Range

    Dual signal generator module outputs 0/4-20mA current and 0-10V voltage with a clear LED display. Useful for PLC testing and troubleshooting; praised for accuracy and ease of use, though build quality and power sourcing receive mixed feedback

    • dual amp & volt output
    • bright LED display
    • back calibration potentiometers
    Check current price on Amazon →
  2. 2
  3. 3
    Healflux Custom Frequency Generator V2

    Healflux Custom Frequency Generator V2

    Tartpe • ★ 3.5/5 • Mid-Range

    A compact frequency generator offering adjustable 0.01 Hz to 20 kHz for Schumann resonance-inspired tones. Aims to enhance relaxation and sleep quality. Customer note: 5.0 rating based on a single review

    • adjustable 0.01 Hz–20 kHz
    • Schumann resonance concept
    • compact personal device
    Check current price on Amazon →
  4. 4
    Upgraded 15MHz DDS Signal Generator Dual-Channel

    Upgraded 15MHz DDS Signal Generator Dual-Channel

    Seesii • ★ 3.4/5 • Mid-Range

    Dual-channel DDS waveform generator with 15 MHz sine output and 200 MSa/s sampling. Stores 99 user states and 60 custom waves for later use. AI note: praised for functionality and readability of display

    • 500kS/s? actually 200 MSa/s sampling
    • store and recall 99 states
    • custom waveform library with 60 saves
    Check current price on Amazon →
  5. 5
  6. 6
    Riiai 4-20mA / 0-24V Current Signal Generator

    Riiai 4-20mA / 0-24V Current Signal Generator

    Riiai • ★ 3.3/5 • Mid-Range

    Riiai signal generator converts 4-20mA to various modes (mA, V, XMT) with adjustable precision. Real-time curve and USB rechargeable, suitable for PLC testing. One customer notes good usability, while another cites accuracy and resistance measurement limits

    • multi-signal-type support
    • precise 0.01mA/0.01V resolution
    • USB rechargeable with presets
    Check current price on Amazon →
  7. 7
    Koolertron DDS Signal Generator Counter 2.8in 80MHz Dual-Channel

    Koolertron DDS Signal Generator Counter 2.8in 80MHz Dual-Channel

    Koolertron • ★ 3.3/5 • Premium

    Compact dual-channel arbitrary waveform generator with mobile app control and data import/export. AI note: users value features and accuracy, though waveform quality feedback is mixed

    • dual-channel high-precision generator
    • mobile app control
    • firmware-friendly with waveform data import/export
    Buy at Amazon →

Buying Guide

Signal type and output ranges

Match the generator's output types (e.g., 4–20mA loop, 0–10V/0–12V DC, PWM, or arbitrary waveform) to your device or test standards to avoid needing external converters

Frequency and waveform capabilities

Choose DDS or arbitrary-waveform units for precise frequency control and complex signals; look for MHz-range models for RF or high-speed bench work

Channels and isolation

Select single- or dual-channel models depending on whether you need simultaneous signals or isolated outputs for differential testing

Interface and control options

Consider generators with easy front-panel controls, digital displays, or external control (USB/PC) if you frequently program sequences or custom waveforms

Build quality and industrial fit

Prioritize units with robust connectors and clear labeling for PLC and field use; look for devices designed for signal injection and loop simulation