PlotJuggler 4: The Rewrite, Explained

PlotJuggler 4 is not a routine version bump. Version 4.0.0, released on 21 September 2026, is a rewrite that turns the best-known open-source time-series plotter into what its documentation calls an extensible, performant, open-source multimodal visualisation platform: time-series and XY plots, yes — but now also time-synchronised video, 3D point clouds and robot models, new file formats such as MCAP and Parquet, Python scripting alongside Lua, and an Extensions Marketplace for plugins. This hub is an independent, unofficial guide to that release — downloads themselves come from the official GitHub releases linked on our Download page.

If you already use PlotJuggler 3, this page also tells you the other half of the story: the PJ3 line is still alive at 3.17.2, it is still the line the ROS ecosystem runs on, and for many ROS users staying on PJ3 for now is the correct decision. The guides below walk through what is new, how the two lines compare, and how to migrate when the time is right.

How PlotJuggler 4 arrived: the release timeline

PJ4 did not appear overnight. It was developed in the open through a 3.999.x preview series during the summer of 2026, before the stable 4.0.0 release in September:

VersionDateWhat it was
3.999.02 July 2026First public PlotJuggler 4 preview build (AppImage only).
3.999.320 July 2026Preview for Windows and Linux: transactional undo/redo, layout schema v4, the Extensions Marketplace and 3D scene fixes.
3.999.910 August 2026Preview: Mosaico cloud download, CSV / Arrow-Parquet export tool, Python scripting as an alternative to Lua, reading of corrupted MCAP files, and OMG IDL / DDS parsing.
4.0.021 September 2026First stable PlotJuggler 4 release, flagged “Latest” on GitHub: Windows installer, x86_64 AppImage and a .deb package.

That timeline matters when you read older coverage: anything written about “PlotJuggler 4” before September 2026 was describing a preview, and searches for the version before then were users hunting an announced rewrite. Since 21 September 2026, the correct answer is simple — 4.0.0 is out, and it is the current version for new, non-ROS installs. Our What’s New in PlotJuggler 4.0 guide covers the release in depth.

The PlotJuggler 4 guides

Who should upgrade — and who should stay on PlotJuggler 3

Your situationRecommendationWhy
New user, no ROS dependencyStart with PlotJuggler 44.0.0 is the current release and the line under active development; install it via the Install guides.
ROS 1 / ROS 2 user relying on rosbag, topic or ROS plugin workflowsStay on PlotJuggler 3 (3.17.2) for nowThe ROS Index still lists the core package at 3.17.2 and the ROS packages are built on the PJ3 line; the ROS ecosystem has not moved to PJ4.
You need video, 3D, MCAP, Parquet or Python transformsMove to PlotJuggler 4Those capabilities exist only in PJ4 — PJ3 has no video or 3D views and scripts transforms in Lua only.
macOS userRead the honest position firstNeither line currently ships a macOS binary: PJ4 4.0.0 has no .dmg, and the last PJ3 release with one was 3.16.0. See the macOS guide.
Curious, but your PJ3 setup worksInstall PJ4 alongside PJ3 and evaluateThe lines use different package names — the PJ4 apt package is plotjuggler4 — so you can trial PJ4 without uninstalling PJ3. See the migration guide.

What PlotJuggler 4 is, in one paragraph

PlotJuggler 4 keeps everything the classic tool was known for — drag signals into time-series and XY plots, load several recordings, align their timelines and overlay them, apply filters, derivatives, integrals and FFT, and save layouts — and extends it in every direction at once. Recorded or live data: files now include MCAP, Parquet and LeRobot alongside CSV and PX4 ULog, and live sources include ROS 2, MQTT, ZeroMQ, UDP, WebSocket and WebRTC. Cameras and sensors join the plots: encoded video in H.264, H.265 and AV1, 2D annotations, and GPU-rendered 3D scenes with point clouds, meshes and URDF models. And the plugin system grows a proper distribution channel, the Extensions Marketplace, backed by a public registry and a plugin SDK (plotjuggler_sdk). PlotJuggler remains free and open source under the Mozilla Public License 2.0 (MPL-2.0), maintained by Davide Faconti.

Getting PlotJuggler 4

PJ4 ships as a Windows installer (per-user, no administrator rights needed), a Linux AppImage (glibc 2.35 or newer), a single-release .deb — and, new in this generation, an official apt repository at apt.plotjuggler.io that keeps Debian and Ubuntu installs updated through normal system upgrades. There is no macOS binary, no aarch64 AppImage and no snap or flatpak for PJ4. Step-by-step instructions for every channel are in the Install hub, and the files themselves — with checksums — are on the Download page.

This site is independently operated and is not affiliated with Davide Faconti or the PlotJuggler project. The official project site is plotjuggler.io.