- 
- 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
-Torque Pro OBD-II logs, lambda delay and acceleration enrichment table generators, TunerStudio MSL imports, RaceChrono lap-timing sessions, GPS track maps, AI-powered analysis via MCP, and more
-Lambda Delay Tables
-A new tool that mines your logs for injector pulse-width steps and measures how long the wideband takes to respond, binned by RPM and load. Every cell carries a sample count and confidence, sparse cells stay blank, and the result exports as CSV, clipboard, PNG or PDF in milliseconds, engine cycles or ignition events — ready for your ECU's closed-loop O2 delay table.
-Accel Enrichment Tables
-Detects tip-ins, shifts the lambda window by the measured delay, and reports the lean or rich excursion against target with a suggested starting correction, binned by RPM and throttle rate. Runs across several logs at once and composes with a lambda delay table generated in the same session.
-TunerStudio MSL Imports
-Open .msl datalogs straight from TunerStudio's legacy ASCII logger — and from RealDash, which writes the same format when it logs a Speeduino over Bluetooth. Units come from the file, GPS columns feed the track map, and cable-free logging sessions load with no conversion step.
RaceChrono Imports
-Open RaceChrono and RaceChrono Pro CSV v3 session exports directly — GPS, phone sensors, and OBD/CAN channels on one timeline, with lap numbers and the track map ready out of the box. Analyze your track days on a big screen instead of your phone.
-Torque Pro Logs
-Open the trackLog CSV files from the Torque Pro OBD-II app for Android. Phone GPS, accelerometer, and every PID Torque logged land on one millisecond timeline, PIDs your car never answered are hidden, and the track map works out of the box.
GPS Track Map
-Logs with GPS channels now draw the track beside your chart — automatic lap detection, any channel painted onto the racing line in Viridis or Turbo, hover to scrub the timeline, and opt-in Esri or OpenStreetMap satellite backgrounds. Works with every supported log format, and coordinate encodings (NMEA, scaled integers) are normalized automatically.
-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
-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
-