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.
What's New in 2.0
A major release with powerful new analysis capabilities and a redesigned interface
Analysis Framework
14 professional analysis algorithms including AFR drift detection, Butterworth filters, volumetric efficiency, and statistical correlation.
2D Histogram View
Visualize channel relationships as interactive heatmaps with configurable grid sizes and real-time cursor tracking.
Font Scaling
Accessibility-focused font sizing with 4 scale options (S/M/L/XL) for improved readability on any display.
Emerald ECU Support
Full support for Emerald K6/M3D ECU binary log files (.lg1/.lg2) with 40+ channel types.
Redesigned UI
VS Code-style activity bar navigation with dedicated panels for files, channels, tools, and settings.
Run & Chart
One-click workflow to run analysis and instantly add results to your chart for immediate visualization.
Multilingual Support
Full internationalization with 15 languages including English, Spanish, German, French, Chinese, Japanese, and more.
Download UltraLog
Available for macOS, Windows, and Linux — always free
Core Features
Everything you need for professional log analysis
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 8 ECU manufacturers with both CSV and binary formats