How to Prepare Spreadsheets and CSV Data for AI Analysis
Clean and shape spreadsheet data so ChatGPT, Claude and Gemini analyze it correctly: headers, sampling, and size limits.
Clean the sheet
Remove merged cells, blank rows, subtotal rows and color-coded meaning. AI reads values, not formatting.
Mind the size
Paste a sample into the Token Counter. Numbers tokenize inefficiently, so thousands of rows add up fast. For notes columns with long text, the Context Compressor helps.
Add a data dictionary
List each column with a one-line description and units. Then ask specific questions rather than 'analyze this'.
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- Context Compressor — Reduce token usage with compression strategies tuned for LLMs.
- Token Counter — Live token, character, and context-window meter for any prompt. Uses official tiktoken encoders.
Tools mentioned
Frequently asked
Can I paste a huge CSV into chat?
Large datasets exceed context quickly. Use the data-analysis feature with a file upload, or paste a representative sample.
Why describe columns?
Abbreviated headers are ambiguous; a short data dictionary prevents misinterpretation.
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