Frequently Asked Questions

Absolutely. Your CSV data never leaves your browser. We use DuckDB WASM, which runs entirely in your browser's memory. Here's what happens:

• Your CSV files are loaded directly into your browser's memory
• All SQL queries execute locally on your device
• No raw data is transmitted to our servers or any third party
• Your data is automatically cleared when you close the browser tab

The only thing we send to our servers is your natural language question (like "Show me revenue by month") and your column names - never the actual data values.

Currently, CSVLens supports CSV (Comma-Separated Values) files.

File requirements:

• Maximum file size: 500MB (browser memory dependent)
• Files should have a header row with column names
• Standard CSV delimiters (comma, semicolon, tab) are auto-detected
• UTF-8 encoding recommended

You can upload up to 5 CSV files simultaneously and join them in your analyses.

Support for Excel (.xlsx), Parquet, and JSON formats is coming soon.

CSVLens uses advanced AI models to convert your natural language questions into SQL queries:

The process:

1. You ask a question in plain English (e.g., "What's the average order value?")
2. We send your question + your table schema (column names and types) to the AI
3. The AI generates the appropriate SQL query
4. The SQL runs locally in your browser against your data
5. Results are formatted and visualized automatically

Agentic Analysis: For complex questions, you can enable "deep analysis mode" where the AI breaks down your question into multiple steps, reasons through the problem, and provides comprehensive insights.

Tokens are units of AI processing. Each time you ask a question, the AI consumes tokens to understand your query and generate SQL.

Token usage by plan:

• Free Tier: 50,000 tokens/month (approximately 150-200 queries)
• Pro Tier: 1,000,000 tokens/month (approximately 3,000-4,000 queries)

What affects token usage:

• Simple queries: ~250-500 tokens
• Complex queries with multiple tables: ~500-1,000 tokens
• Agentic analysis (deep mode): ~2,000-5,000 tokens

Your current usage is always visible in the dashboard, and you'll receive alerts when approaching your limit.

Yes! CSVLens offers multiple export options:

Free Tier:

• Copy results to clipboard (tables and charts)
• Download query results as CSV
• Copy generated SQL queries
• Screenshot individual charts (browser built-in)

Pro Tier (additional):

• Export charts as high-resolution PNG images
• Export entire dashboards as PDF reports
• Batch export multiple visualizations
• Export with custom branding

You can load and analyze multiple CSV files simultaneously:

• Free Tier: Up to 5 datasets
• Pro Tier: Unlimited datasets

Cross-dataset analysis: You can join data across multiple tables, run aggregations, and create combined visualizations. For example: "Join sales_data with customer_data on customer_id and show total revenue by region."

The only limit is your browser's memory. Most modern browsers can handle hundreds of megabytes of data.

Not at all! That's the whole point of CSVLens.

Just ask questions naturally:

• "What's the average order value?"
• "Show me monthly revenue for 2024"
• "Which customers spent the most?"
• "Compare sales between regions"

But if you do know SQL: You can view and edit the generated SQL queries. This is great for:

• Fine-tuning AI-generated queries
• Learning SQL by seeing examples
• Running custom queries directly

Dashboard Sharing: You can create dashboards by pinning your favorite queries and charts. These can be exported as PDF reports (Pro tier).

Coming Soon:

• Team workspaces for collaboration
• Shareable dashboard links
• Real-time collaboration on analyses
• Role-based access control
• SSO for enterprise teams

Team features are currently in development. Join our waitlist to get early access!