Violin Plot
Compare data distribution and probability density simultaneously.
About Violin Plot
A violin plot is a method of plotting numeric data. It is similar to a box plot, with the addition of a rotated kernel density plot on each side. It shows the full distribution of the data, including the probability density at different values.
How to Use
- Paste raw datasets — copy one or more columns of numeric data from your spreadsheet.
- Kernel density calculation — the tool automatically computes the probability distribution.
- Identify multimodal data — easily see if your dataset has multiple peaks or unusual clusters.
- Compare groups — plot multiple violins side-by-side for multivariate analysis.
- Export — download as a high-density PNG or professional SVG.
Common Use Cases
- Advanced Statistics — analyze experimental results where the distribution shape matters as much as the median.
- Demographic Surveys — visualize the distribution of income or age across different segments.
- Machine Learning — monitor feature distributions and identify data drift or bias.
- Quality Control — detect subtle manufacturing variations that a simple box plot might miss.
Technical Details
Powered by Apache ECharts. Implements a client-side Kernel Density Estimation (KDE) algorithm for precise shape rendering.
Frequently Asked Questions
- What is the difference between a Violin Plot and a Box Plot?
- A box plot only shows summary statistics (min, max, median, etc.), while a violin plot shows the entire shape of the data distribution.
- What data is a violin plot best suited for?
- Violin plots are ideal for comparing the probability distribution of a numeric variable across multiple groups — for example, response time distributions across server regions, test score distributions across classrooms, or salary distributions across job grades. They are especially useful when the distribution is multimodal (has multiple peaks), which box plots cannot reveal.
- How do I export my violin plot to PowerPoint?
- Click 'Download PPTX'. The violin plot is exported as a high-resolution image embedded in a PowerPoint slide. The mirrored density curves and optional embedded box plot are preserved exactly as displayed, making it suitable for academic conference presentations and data science reports.
- How should I format data for a violin plot?
- Paste a table where each column represents one group (with a header as the group name) and the rows below contain the raw numeric observations for that group. Groups can have different numbers of observations — just leave cells empty for shorter groups. The tool computes the kernel density estimate automatically from the raw values.
- Is my data processed securely?
- Yes. All kernel density estimation and violin plot rendering happen client-side in your browser. Your raw observation data is never uploaded to any server, making this tool safe for sensitive research, clinical trial, and HR datasets.
- Can I overlay a box plot on top of the violin plot?
- Yes. The Violin Plot tool has an option to overlay a box plot (showing median, quartiles, and whiskers) on top of the violin shape. This combined view is popular in scientific publications because it shows both the full distribution shape (from the violin) and the key summary statistics (from the box plot) simultaneously. You can toggle the box overlay on or off from the chart options panel. The combined chart exports as PNG, SVG, or PowerPoint and is rendered by Apache ECharts in your browser.
Chart Data in PNG — Resume Editing
What is embedded chart data?
PNG exports and shared links may include your original chart data and settings. Anyone with the file or complete link may recover them.
How to use it
- Export your chart to PNG
- Keep the PNG file
- Drop or paste it into the "Resume Chart from PNG" tool any time you need to edit it again
- Your chart restores exactly as you left it — make changes and export again
Why this is better than static images
Other chart tools export PNG images that are final — once exported, you cannot edit them without redoing the work from scratch.
- No need to save the source spreadsheet separately — the PNG IS your backup
- Share a PNG with a colleague and they can restore and edit it without the original data
- Years later, if you need to update a chart, open the PNG and resume — no searching for old files
- For archival: keep PNGs alongside your reports and presentations; they are fully self-contained
Is it secure?
PNG exports and shared links may include your original chart data and settings. Anyone with the file or complete link may recover them.
Embed URL — Interactive Chart for Presentations
What is the Embed URL?
The Embed URL opens a clean, interactive version of your chart in a browser — showing only the chart with no tool interface, no settings panel, and no export buttons. Tooltips and hover interactions work fully. The chart data is encrypted in the URL, just like the Recovery Link.
Where to find it
- Click the "🔗 Embed URL" button on the chart tool page — it copies the URL to your clipboard instantly
- The embed URL is also saved below the slide boundary in your exported PPTX file, labeled "Embed URL — interactive view"
Using the Embed URL in Other Tools
The Embed URL works anywhere that supports iframes or URL embeds:
- Notion — paste the URL as an embed block (type /embed in Notion)
- Confluence — use the HTML macro or iframe macro with the embed URL
- SharePoint — embed via the Embed web part
Any website or intranet page — use a standard HTML iframe:
<iframe
src="YOUR_EMBED_URL"
width="800"
height="500"
frameborder="0"
allowfullscreen>
</iframe>Note on self-hosted deployments: If your organisation uses the self-hosted version of Lokaltools on your intranet, embed URLs point to your internal domain. These will only work for viewers on your company network or VPN — which may be exactly what your IT security team requires.
Chart Colors — Brand-Consistent Palettes in Seconds
Most charting tools give you a fixed color palette you cannot change, or require you to manually pick every color one by one. Lokaltools uses a three-step color system that starts from your company's brand color and builds a complete, harmonious palette automatically.
Step 1 — Brand Anchor
Enter your company's primary brand color as a hex code (e.g. #0066CC) in the Brand Anchor field. This is typically your main logo color, primary button color, or the dominant color from your brand guidelines. The brand anchor color is used as the starting point for all palette generation. Every color in your chart traces back to this single input — so your chart always feels on-brand without manual color selection.
Step 2 — Harmony
The Harmony dropdown selects the color theory rule used to generate the remaining chart colors from your brand anchor. Each harmony produces a different relationship between colors.
| Harmony | What it produces | Best for |
|---|---|---|
| Analogous | Colors adjacent on the color wheel — subtle, cohesive | Single-theme data, when colors should feel similar |
| Complementary | Two colors directly opposite — high contrast | Two-series comparisons, positive vs negative |
| Triadic (Balanced) | Three evenly spaced colors — vivid but balanced | Most business charts, 3-6 data series |
| Split Complementary | One anchor + two colors flanking its complement | Good contrast without full complementary tension |
| Tetradic | Four colors forming a rectangle on the wheel — rich | Charts with 4+ series needing maximum distinction |
Triadic (Balanced) is the default and works well for most business presentations. Switch to Analogous for a more subtle, conservative look, or Complementary when you want two data series to visually contrast strongly (e.g. budget vs actual).
Step 3 — Generated Swatches (Manual Override)
Below the harmony selector, the tool displays 5–6 generated color swatches — these are the actual colors that will appear on your chart. If any individual color does not work, click that swatch to open a color picker and replace it with any color you choose. Manual overrides are preserved in the recovery link.
Background mode (Light / Dark toggle): switches the palette lightness to suit your slide background. This adjusts the generated colors automatically so they remain readable.
Tips for Brand Color Usage
- Finding your exact brand hex code: Check your company's brand guidelines PDF, or right-click your company logo on the website → Inspect → find the CSS color value.
- When to use Analogous vs Triadic: Use Analogous when your chart has one dominant message and you want colors to feel unified. Use Triadic when each series represents a genuinely different thing (e.g. Revenue, Cost, Profit).
- Matching exported chart colors to your PowerPoint template: The PPTX Exact export preserves colors pixel-perfectly — what you see in the browser is exactly what appears in your PowerPoint slide.
Frequently Asked Questions
- Does this tool work offline?
- Yes — once the page has loaded, the tool works fully without an internet connection. The only exception is the Embed URL interactive view, which requires the chart tool page to be reachable when the embed is displayed.
- Can I use this for confidential or sensitive data?
- Yes. Your data is processed entirely in your browser using WebAssembly. It is never sent to Lokaltools servers or any third party. This makes the tool suitable for financial data, patient data, legal documents, and any other sensitive information.
- What data formats can I paste?
- Copy cells directly from Excel, Google Sheets, or Apple Numbers and paste — the tool auto-detects the format. CSV file upload is also supported. Data copied from web pages or PDFs may not paste correctly — clean it in Excel first.
- How do I find my company's brand hex color?
- Check your company's brand guidelines document or open your company website, right-click the logo or a branded button, select "Inspect", and look for a CSS color value starting with #.
- Can I save my brand color so I don't have to re-enter it every time?
- The brand anchor color is saved in the Recovery Link along with all other chart settings. Export your chart, then use the Recovery Link next time to restore your brand color automatically.
- Is the embedded chart data permanent?
- Yes. The embedded data is stored in the PNG file itself — not on any server — so there is no expiry. As long as you have the PNG file, you can restore and edit your chart.
- Can I share the PNG with a colleague?
- Yes — anyone with the PNG file can restore and edit the chart using the "Resume Chart from PNG" tool. Treat the PNG like a shared document: share only with people who should have access to the underlying data.
- What is the difference between embedded PNG data and Embed URL?
- Embedded PNG data contains your full chart state encrypted in the PNG file — you can drop it into the "Resume Chart from PNG" tool to edit and re-export. The Embed URL opens a view-only interactive chart with no editing capability.
Privacy & Security
This tool runs entirely in your browser. Your data follows this path: Your spreadsheet → Your browser → Your exported file. Nothing else. No upload step. No server processing. No analytics on your data content.
Chart PNG exports may contain the original chart data and settings as recoverable metadata. Recovery and embed links contain data and the key needed to open it in the URL fragment. Anyone with the file or complete link may recover that data. Share only with intended recipients. A fragment is normally omitted from HTTP requests, but JavaScript and services you share a link with can read it.
For organisations requiring formal confirmation: Lokaltools cannot read your data, does not store your data, and has no technical mechanism to access your data even if legally compelled to do so. This is not a policy — it is an architectural fact.
Technical Details
Powered by Apache ECharts for high-performance canvas rendering, PapaParse for intelligent CSV and tab-separated data parsing, and PptxGenJS for native OOXML chart objects. Magic link encryption uses the browser's built-in Web Crypto API (AES-256-GCM) with pako compression — no external encryption library required. All processing is 100% client-side. No data is transmitted at any point.
Local processing
Our local file, text and chart tools process content on your device using JavaScript, browser APIs and, where needed, WebAssembly. Our usage events do not include filenames, file contents, input text, chart values, raw errors, emails or license references. Network lookup tools (such as DNS, WHOIS, IP and speed tests) contact external services for their stated purpose. Loading the website, fonts, libraries and models also makes network requests. WebAssembly itself does not prevent network access.