Frequently Asked Questions

VizFlow is a free, client-side data visualization tool built by Sidequest Labs. It lets you drag-and-drop CSV, TSV, or JSON files and instantly create beautiful, interactive charts.

Everything runs in your browser — no server uploads, no sign-up required. Your data never leaves your device.

Yes. VizFlow's core features are completely free and will always be free. This includes:

• All 9 base chart types (Bar, Line, Scatter, Pie, and more)
• CSV, TSV, and JSON import
• 4 built-in color palettes
• Dark and light themes
• PNG export
• Share via URL and embed code generator
• Data transformation tools (sort, filter, aggregate)
• Undo / redo

For advanced chart types, dashboard mode, and high-res export, see Pro plans.

No. VizFlow requires no account, no email, and no sign-up. Just open the app, drop your file, and start visualizing.

If you purchase a Pro plan, you will receive a license key via email after checkout. You enter that key directly in the app — no account system involved.

VizFlow supports the following input formats:

• CSV (Comma-Separated Values) — the most common tabular format
• TSV (Tab-Separated Values)
• JSON (array of objects)

You can also paste data directly into the app if you have tabular text on your clipboard. The parser auto-detects delimiters.

There are two ways to load data into VizFlow:

1. Drag and Drop — Drag a CSV, TSV, or JSON file from your file manager directly onto the upload area.
2. File Picker — Click the upload area or the file input to open your system's file browser and select a file.

The file is parsed entirely in your browser. Nothing is uploaded to any server.

Since VizFlow runs entirely in your browser, the practical file size limit depends on your device's available memory.

Most modern browsers can comfortably handle datasets with tens of thousands of rows. For extremely large files (100,000+ rows), you may notice slower initial parsing depending on your hardware.

If performance is an issue, try filtering or aggregating your data before import.

Yes. Below the upload area you will find a text area where you can paste tabular data directly from your clipboard — copied from a spreadsheet, email, or any text source.

VizFlow auto-detects the delimiter (comma, tab, semicolon) and column structure. After pasting, click Load to import the data.

VizFlow offers 12 chart types total:

• Bar — Compare categories side by side
• Stacked Bar — Part-to-whole across categories
• Line — Track trends over time
• Scatter — Find correlations in your data
• Bubble — Three dimensions in one view
• Pie — Parts of a whole at a glance
• Doughnut — Modern take on the classic pie
• Polar Area — Compare categories by area
• Radar — Multi-dimensional comparison

All 9 base chart types are available on the free tier.

Use the Chart Type selector in the sidebar. After loading your data, click any chart type to instantly switch. VizFlow animates the transition between chart types.

VizFlow also provides Smart Recommendations — it analyzes your data shape and suggests the best chart type with reasoning. One click to apply the suggestion.

Pro unlocks 4 additional advanced chart types:

• Waterfall — Visualize cumulative changes from a baseline (ideal for financial data)
• Funnel — Show progressive stage reduction (sales pipelines, conversion flows)
• Treemap — Display hierarchical data as nested rectangles
• Sankey — Illustrate flow distribution between categories

These are available with any Pro plan.

Yes. VizFlow includes 4 built-in color palettes on the free tier. Switch between them from the sidebar to instantly update your chart's look.

Pro users get access to a full color picker for per-series customization, plus the ability to save and load custom themes from local storage.

Yes. Click on any column header in the data preview table to rename it. The chart will update automatically to reflect the new label.

You can also rename axis labels and series names directly from the chart configuration panel.

The chart title is editable directly in the configuration panel. Type your custom title and it will appear at the top of the chart in real time.

You can also toggle the title on or off, and customize axis labels and number formatting (currency, percentage, compact notation) with a Pro plan.

Yes. PNG export is available on the free tier. Click the Export button to download your chart as a PNG image.

Pro users get access to high-resolution PNG export with customizable dimensions, perfect for presentations and print.

Batch export is a Pro feature that lets you export in multiple formats at once:

• PNG — Standard resolution image
• HD PNG — High-resolution image for print
• CSV — The underlying data
• JSON — Chart configuration and data

In dashboard mode, you can export the entire multi-chart layout as a single composite image.

VizFlow offers two ways to share:

• Share via URL — Compress your entire chart state (data and configuration) into a shareable URL. One click to copy. No server needed.
• Embed Code — Generate an iframe embed code with customizable dimensions and responsive mode. Perfect for blogs and documentation.

Both features are available on the free tier. The URL contains all the data encoded client-side — nothing is stored on a server.

Yes. VizFlow includes full sort and filter capabilities:

• Multi-level sorting — Sort by one or more columns in ascending or descending order.
• 11 filter operators — Equals, not equals, contains, starts with, greater than, less than, and more.

Sorting and filtering update the chart in real time so you can see the effect immediately.

Yes. VizFlow supports group-by aggregation. Choose a column to group by and a numeric column to aggregate, then select the aggregation function:

• Sum — Total of all values in the group
• Average — Mean value per group
• Count — Number of rows per group
• Min / Max — Lowest or highest value per group

This is useful for summarizing large datasets before charting.

No. Your data never leaves your browser.

VizFlow is a fully client-side application. Every operation — import, visualization, transformation, and export — runs entirely in your web browser using JavaScript. No data is ever uploaded, transmitted, or stored on any server.

This applies to all features, including the free tier and Pro features. Your files stay on your machine at all times.

Yes. VizFlow is a Progressive Web App (PWA). After your first visit, the browser caches the app's files so it can load without an internet connection.

To enable offline use:

1. Visit vizflow.app while online.
2. The browser will automatically cache the app files in the background.
3. You can also click "Install" to add VizFlow to your home screen or desktop.

Once cached, VizFlow works fully offline. All chart creation, customization, and export operations function without any network connection.

Pro unlocks all features beyond the free tier, including:

• 4 advanced chart types (Waterfall, Funnel, Treemap, Sankey)
• Multi-chart dashboard mode with templates and save/load
• Custom color picker and theme builder
• High-resolution PNG export
• Export dashboard as composite image
• Number formatting (currency, percentage, compact notation)
• Axis label customization
• Batch export (PNG, HD, CSV, JSON)
• Priority support

See the full Free vs. Pro comparison for details.

To upgrade to Pro:

1. Visit the Pricing section on the landing page and choose a plan (Lifetime or Monthly).
2. Complete the checkout process via Stripe.
3. You will receive a license key by email.
4. Open the VizFlow app and click "Pro" in the header.
5. Enter your license key. It will be validated and stored locally in your browser.

Once activated, all Pro features are immediately available. You do not need to create an account.

All payments are processed securely through Stripe. Accepted payment methods include:

• Visa, Mastercard, American Express, Discover
• Debit cards
• Apple Pay and Google Pay (where available in your browser)

VizFlow never sees or stores your payment information. Stripe handles all card details directly.

Monthly plan: Yes, you can cancel at any time. Your Pro access will remain active until the end of your current billing period. You can cancel from your Stripe customer portal, which is linked in your purchase confirmation email.

Lifetime plan: The Lifetime plan is a one-time payment — there is nothing to cancel. You have access to Pro features forever, including all future updates.

In both cases, if you cancel, your license key remains valid until its expiration date. After that, the app gracefully falls back to the free tier.

If your chart appears empty after loading data, try these steps:

1. Check column assignments. Make sure the correct columns are assigned to the X-axis and Y-axis in the sidebar configuration.
2. Check data types. Ensure numeric columns are recognized as numbers, not text. VizFlow auto-detects types, but you can manually override them.
3. Check for empty rows. If most rows are blank, the chart may appear empty. Try filtering out empty rows first.
4. Try a different chart type. Some chart types require specific data shapes (e.g., Pie needs a single numeric series).

If your file does not load, try these steps:

1. Check the file format. VizFlow supports CSV, TSV, and JSON. Other formats (XLSX, PDF, XML) are not supported.
2. Check the file encoding. The file should be UTF-8 encoded. If your file uses a different encoding, try converting it to UTF-8 first.
3. Check for malformed data. Malformed CSV (unclosed quotes, inconsistent column counts) may cause parsing errors. Try opening the file in a plain text editor to inspect its structure.
4. Try pasting instead. Open the file in a text editor, copy the contents, and paste into VizFlow's text area.

If the issue persists, please open a GitHub issue on the Sidequest Labs repository with a description of the problem.

VizFlow automatically detects your system's color scheme preference and applies light or dark mode accordingly. If dark mode does not appear to be working:

1. Check your OS setting. VizFlow follows your operating system's appearance setting (Light/Dark). On macOS, this is in System Settings > Appearance. On Windows, it is in Settings > Personalization > Colors.
2. Check your browser. Some browsers allow overriding the system preference. Ensure your browser is not set to force a specific color scheme.
3. Clear cached data. Try clearing your browser cache for the VizFlow site, then reload.
4. Try incognito mode. Open VizFlow in an incognito or private window to rule out extension interference.

Custom theme settings (available in Pro) override the system preference. If you previously set a custom theme, you can reset it from the theme picker in the app settings.