Chart.js vs uPlot
Which should you use? A side-by-side look at what each one does, who it suits, what it costs, how hard it is to set up, and where each falls short.
Open source · MIT
A JavaScript library for drawing simple, customizable charts on web pages using canvas.
Open source · MIT
A small, fast JavaScript chart library for time series, lines, areas, OHLC and bars.
The short answer
Choose Chart.js if you need…
- Web developers adding standard charts such as line or bar charts to a site
- Designers who want chart styling they can configure in code
- Teams building dashboards in the browser who want an MIT-licensed library
Choose uPlot if you need…
- Web developers who need a fast chart for large time series data
- Dashboards that update live with streamed data
- Apps where a small download size matters
- Projects that need zoom and cursor sync across multiple charts
Side-by-side
| Chart.js | uPlot | |
|---|---|---|
| Type | Library | Library |
| Price | Free and open source | Free and open source |
| Licence | MIT | MIT |
| GitHub stars | 67.8k | 10.6k |
| Setup difficulty | Intermediate | Intermediate |
| How you get it | See the README | Install with a package manager |
| Main language | JavaScript | JavaScript |
| Last code update | 14 days ago | 6 days ago |
What each one is
Chart.js
Chart.js is a JavaScript library for adding charts to web pages. It draws charts on the HTML canvas element, so you pass it data and options and it renders the graphic in the browser. People use it to show data visually on websites and dashboards without building chart rendering from scratch.
uPlot
uPlot is a JavaScript library that draws charts in a web page using the browser's Canvas 2D drawing API. It is built for plotting time series data such as lines, areas, OHLC and bars. The README says it is about 50 KB minified and aims to render large datasets quickly with low memory use.
Best for
Chart.js
- Web developers adding standard charts such as line or bar charts to a site
- Designers who want chart styling they can configure in code
- Teams building dashboards in the browser who want an MIT-licensed library
uPlot
- Web developers who need a fast chart for large time series data
- Dashboards that update live with streamed data
- Apps where a small download size matters
- Projects that need zoom and cursor sync across multiple charts
Strengths
Chart.js
- MIT licensed, so it can be used in commercial and open-source projects
- Large community with a documentation site, samples, and a Discord server linked from the README
- Actively maintained, with a recent release (v4.6.1) and a recent last push
uPlot
- The README reports strong benchmark results against other chart libraries, with a small bundle size
- Supports time zones (IANA names) and daylight saving time, plus features like missing data handling and high/low bands
- Has a plugin and hooks API for extending behavior
Not ideal for
Chart.js
- People who need a finished chart tool with no coding, since this is a library that requires writing JavaScript
- Projects needing chart types or features the README does not describe, since the README here gives little detail on specific chart types
- Users who need charts rendered on a server, since the README describes browser canvas usage
uPlot
- People who want a ready-made chart with no coding, since the README focuses on the API and docs are described as a work in progress
- Projects needing built-in drag panning, since the README says it is not included and must be added via plugins
- Very large live views above about 100k points, which the README says may struggle
- Projects needing 3D or WebGL-style rendering, since the README points to other libraries for that
Trade-offs
Chart.js
- Requires JavaScript and web page knowledge to use, so it is not beginner-friendly for non-coders
- The README is short and points to external docs for details, so getting started depends on those docs
- Documentation links in the README point to version 4; older versions need separate docs URLs
uPlot
- The README says the docs are a work in progress, so some APIs need to be learned from the type definitions and demos
- Does not include data parsing, aggregation or statistics, and has no animations or built-in panning
- Axis tick labels have no collision avoidance, so spacing may need manual tuning
Getting started
Chart.js
Clone the repository
git clone https://github.com/chartjs/Chart.jsuPlot
Clone the repository
git clone https://github.com/leeoniya/uPlotFrequently asked questions
What is the difference between Chart.js and uPlot?
Chart.js: A JavaScript library for drawing simple, customizable charts on web pages using canvas. uPlot: A small, fast JavaScript chart library for time series, lines, areas, OHLC and bars. Chart.js suits web developers adding standard charts such as line or bar charts to a site, while uPlot suits web developers who need a fast chart for large time series data.
Are Chart.js and uPlot free?
Chart.js: Free and open source. uPlot: Free and open source.
Is Chart.js or uPlot more popular?
Chart.js has more GitHub stars (67.8k) than uPlot (10.6k). Popularity isn't the same as fit — check which one matches your use case above.
What are other alternatives to Chart.js and uPlot?
Other options people compare them with include Plotly.js, Frappe Charts, G2, three.js, Sigma.js.
Keep comparing
Built from our catalogue entries for both products: open-source details come from each project's README (AI-assisted, refreshed weekly) and GitHub data; AI-tool details are editorial. Spotted something wrong? Let us know from either product's page.