Modbus Simulator

Test, debug, and simulate Modbus devices with the industry's most complete all-in-one tool. Master + Slave modes included — no subscriptions, no hidden fees, no separate purchases.

Both Modes Included Master + Slave in one app (competitors charge separately)
One-Time Payment Pay $99 once, use forever (no monthly fees)
All Protocols TCP, UDP, RTU, ASCII + 4 hybrid modes
14Function Codes
8Protocol Variants
4 NEWDiagnostic Tools
$0/monthForever

See It in Action

A modern, intuitive interface for professional Modbus testing and simulation.

Modbus Simulator - Master Mode with data grid and live polling
Modbus Simulator - Address Scanner discovering devices Address Scanner
Modbus Simulator - Live data charts Live Charts
Modbus Simulator - Connection settings Connection Setup

🎉 NEW in v1.1.1: Advanced Diagnostic Features

Professional-grade diagnostic tools now included — capabilities that competitors charge extra for or don't offer at all

🔍

Raw Frame Analysis

See the actual protocol bytes in your communication log. Every TX/RX frame displayed in hex format for deep protocol inspection.

TX: 01 03 00 00 00 0A C5 CD
RX: 01 03 14 00 00 00 01...
⚠️

Exception Response Testing

Inject Modbus errors in Slave mode to test your Master's error handling. Choose from 11 exception codes with 4 flexible trigger modes.

  • Always inject
  • Every Nth request
  • Random percentage
  • Specific function code
📊

Advanced Polling Strategies

Optimize data collection beyond simple fixed intervals. Burst mode for rapid sampling, Adaptive mode auto-adjusts to network conditions.

  • Fixed: Traditional constant interval
  • Burst: Rapid polls with pauses
  • Adaptive: Auto-adjusts to latency
🔬

Frame-Level Diagnostics

Click any frame for deep analysis. Automatic parsing, CRC validation for RTU, field-by-field breakdown, error detection.

  • Parse TCP/RTU/ASCII frames
  • Validate CRC checksums
  • Detect malformed frames
  • Identify exceptions

🚀 These Features Are Included FREE

Competitors either don't have them or charge $50-100+ extra for similar diagnostic tools

Why Is It Only $99?

Direct pricing. No marketing overhead. No subscriptions. Just great software.

Typical Competitors

Expensive
Master Tool: $129
Slave Tool: $129
+
Annual Support: $89/year
Year 1 Total: $347
3-Year Cost: $525
  • ✗ Separate Master & Slave licenses required
  • ✗ Limited protocol support
  • ✗ Annual support fees
  • ✗ Fewer function codes

Modbus Simulator

Best Value
Master + Slave: $99
Lifetime Updates: $0
+
Forever Support: $0
Year 1 Total: $99
3-Year Cost: $99
  • ✓ Both modes included FREE
  • ✓ 8 protocol variants (most in industry)
  • ✓ Free updates forever
  • ✓ 14 function codes (industry-leading)
Save $426 over 3 years — and get more features than competitors offer

Everything You Need for Modbus Testing

One tool. Both sides of the protocol. Full visibility. Master + Slave included — competitors charge separately.

8 Protocol Variants

TCP, UDP, RTU, ASCII, RTU-over-TCP, ASCII-over-TCP, RTU-over-UDP, ASCII-over-UDP. RS-485 RTS toggle and local echo support.

14 Function Codes

FC01-06, FC08 Diagnostics, FC11 Event Counter, FC15/16 multi-write, FC17 Report Server ID, FC22 Mask Write, FC23 Read/Write, FC43 Device Info.

Live Data Charts

Real-time line charts with up to 8 simultaneous address traces. Color-coded, auto-scrolling, time-based display.

21+ Display Formats

16-bit signed/unsigned/hex/binary/BCD, 32-bit float (4 byte orders), 64-bit double, 32/64-bit long, and ASCII string.

Data Logging & Export

Log to CSV or XLSX in real-time. Print or export to PDF. REST API for Excel/VBA integration. Full communication logger with TX/RX hex data.

Advanced Diagnostics ✨ ENHANCED

NEW: Raw frame analysis, exception injection, burst/adaptive polling, frame-level diagnostics. PLUS: Test Center, Address Scanner, color rules, scaling/offset, broadcast mode, ENRON/DANIEL addressing.

Two Modes. One Application.

Master Mode

Poll & Control Devices

  • Connect via TCP, UDP, RTU, ASCII, and all cross-framing variants
  • Configure multiple simultaneous polls
  • 14 function codes including diagnostics and device info
  • Write single or multiple coils and registers
  • Address scanner and raw frame test center
  • Broadcast support (Slave ID 0) and ENRON/DANIEL addressing
Slave Mode

Simulate Devices

  • Emulate a Modbus slave for testing masters
  • TCP, UDP, RTU, and ASCII server modes
  • Configurable memory: up to 10,000 registers per type
  • Edit register values in real-time
  • View incoming request log with function codes
  • Configurable slave ID

Flexible Data Display

21+ display formats with 4 byte-order options. Scaling, offset, and conditional color rules.

Unsigned
Signed
Hex
Binary
BCD
Float32
Float64
Long32
Long64
ASCII String

Simple, Honest Pricing

Pay once. Own forever. No subscriptions. No annual fees. No hidden costs. Both Master & Slave modes included.

3+ Licenses
$79
per license · one-time
  • Everything in single license
  • 20% volume discount
  • Separate key per user
  • Team onboarding support
  • Priority email support
What You Get for $99:
Master Mode (worth $129 elsewhere)
Slave Mode (worth $129 elsewhere)
4 Advanced Diagnostic Tools ($50-100 value, not available elsewhere)
All 8 Protocols (TCP, UDP, RTU, ASCII + hybrids)
All 14 Function Codes (competitors have 8-10)
Lifetime Updates ($89/year value)
Email Support Forever (no expiry)

Get Started

Download includes a 15-day free trial. No credit card required.

Download Now

Windows 10/11 · 64-bit · 118 MB