Unlock Your Performance Data

A high-performance, cross-platform ECU log viewer built with Rust. Analyze your datalog files with blazing speed, powerful analysis tools, and beautiful visualizations. Free and open source — no subscriptions, no licenses.

New v2.9.0 Open Source

What's New

Stacked plots, AI-powered analysis via MCP, BlueDriver OBD-II support, and more

Stacked Plot Areas

Split your chart into up to 10 independent panels — each with its own Y-axis, channels, and scale. Resize, collapse, and rearrange with a shared synchronized timeline.

MCP Server for AI

Built-in Model Context Protocol server lets Claude Desktop control UltraLog — load files, select channels, compute formulas, and analyze data with 23 AI tools.

BlueDriver OBD-II

New parser for BlueDriver Bluetooth OBD-II scanner CSV exports — analyze standard OBD-II PIDs from any compliant vehicle.

AFR/Lambda Units

New unit preference for Air-Fuel Ratio and Lambda display — switch between AFR and Lambda across all mixture channels.

Analysis Framework

14 professional analysis algorithms including AFR drift detection, Butterworth filters, volumetric efficiency, and statistical correlation.

15 Languages

Full internationalization with 15 languages including English, Spanish, German, French, Chinese, Japanese, and more.

Upgraded Engine

Rust 1.94.1, egui 0.34, rewritten PDF export, and updated dependencies for better performance and stability.

Download UltraLog

Available for macOS, Windows, and Linux — always free

macOS
Apple Silicon (M1/M2/M3/M4)
Download DMG
macOS
Intel Macs
Download DMG
Windows
Windows 10/11 (64-bit)
Download ZIP
Linux
x86_64 Binary
Download TAR.GZ

Core Features

Everything you need for professional log analysis

Stacked Plots

Split your chart into independent panels with separate Y-axes. Compare RPM and Lambda side-by-side without scale conflicts.

Interactive Charts

Beautiful, responsive charts with zoom, pan, and multi-channel overlay. Plot up to 10 channels simultaneously.

Blazing Fast

Built with Rust for maximum performance. Load and analyze large log files instantly with LTTB downsampling.

Scatter Plots

Visualize correlations between any two channels with interactive XY scatter plots.

Computed Channels

Create virtual channels with mathematical formulas and time-shifting like RPM[-1] or Boost@-0.5s.

Playback Mode

Play through your logs in real-time with adjustable speed from 0.25x to 8x.

Multi-File Tabs

Open multiple log files in Chrome-style tabs for easy comparison and analysis.

Export Options

Export charts as PNG images or PDF documents for reports and sharing.

Unit Conversion

Toggle between metric and imperial units on the fly across 8 unit categories.

Colorblind Mode

Wong's optimized color palette for accessibility and clear channel differentiation.

Field Normalization

Standardize channel names across ECU systems for consistent cross-platform comparison.

Min/Max Legend

See peak values for each channel at a glance with the min/max legend overlay.

Auto Updates

Stay current with automatic update notifications and one-click installation.

Supported ECUs

UltraLog supports 10 ECU manufacturers with both CSV and binary formats

Haltech ECUMaster EMU Pro RomRaider Speeduino rusEFI AiM (XRK/DRK) Link ECU (LLG) Emerald K6/M3D MegaSquirt BlueDriver OBD-II