Option A: ChatGPT: tabulates with visible code and drafts the brief
Best when: You want to inspect the exact code behind every number
What it does: ChatGPT tabulates and drafts; you audit the code
Strong at: Python code, outputs and assumptions are reviewable
Limit: Vendor warns the first method or chart may mismatch intent
Free plan: Yes
Option B: Julius AI: tabulates and drafts, you recompute
Best when: You want conversational tabulation plus ledger and brief drafting
What it does: Julius AI tabulates and drafts; you recompute numbers
Strong at: Plain-language requests with CSV export
Limit: No inspectable code shown; every number needs recomputing
Free plan: Yes, limited (75 one-time + 25 daily credits)
Option C: Gemini: computes inside the spreadsheet you audit
Best when: You want to audit every number inside the spreadsheet itself
What it does: Gemini computes in the workbook; you verify in place
Strong at: Computation and checking happen in one artefact
Limit: Gemini may read only a sample of rows; full-data checks needed
Free plan: Yes