A finance analyst inherits a forecast workbook and needs help tracing assumptions rather than generating a persuasive unsupported narrative. Here is a scenario-based comparison using documentation checked on 2026-10-25, not an independently tested vendor ranking. The region, plan, exact model version and price are unspecified unless a first-party document establishes them; unmatched performance claims stay unknown.
Audience: FP&A and spreadsheet teams. Evidence checked: 2026-10-25. Editorial status: ready. Comparison scope: named scenario; region, plan and model/version parity require separate confirmation.
Explain a cell, not just the dashboard
A forecast explanation should state where an output came from: input assumptions, formulas, joins, date ranges and manual overrides. Microsoft documents formula explanation and spreadsheet insight tasks. Google documents formula creation and insights in Sheets. Neither description confirms that a generated narrative has audited every dependency, hidden sheet or circular reference. Build a structured audit of source ranges first; use assistants to propose explanations that analysts verify.
An effective side-by-side fixture
Prepare a small revenue model with six months of actuals, five scenarios, one broken link and one hidden override. Ask each assistant to locate why cash balance differs after a forecast change, explain the sensitivity and output cell references. Recalculate with conventional spreadsheet formulas, not a model-generated number. A plausible answer without traceable references fails. Test that table transformations do not overwrite formulas, formatting or named ranges.
Portability is a selection constraint
Excel and Sheets represent formulas, permissions, versioning and external data differently. A migration that changes a function or number format can change the financial answer regardless of the assistant. Evaluate within the organization’s native spreadsheet first, then test any necessary export and import path. Google’s own guide specifies that Gemini in Sheets works best with native Sheets files, which is a workflow caveat rather than proof that all Excel features transfer cleanly.
Control the story before releasing it
Require a reviewer to sign off input ranges, accounting conventions, FX assumptions and calculation dates. The assistant’s prose should identify uncertainties and material adjustments instead of presenting confidence without evidence. For pricing and plan eligibility, consult dated AI 10 snapshots. Neither vendor document constitutes an independent accuracy benchmark; measure rework time in the approved company template.
What an actual buyer pilot should measure
Freeze the relevant source files, release identifiers, evaluation prompts, operator permissions and reviewer identities. Use the same rights-cleared materials for every candidate; separate tasks that cannot be configured equivalently instead of forcing them into a single ranking. Review the resulting artifacts against objective acceptance criteria specific to this decision: source traceability, error handling, rework, permission boundaries and whether a competent human approves the final deliverable. Record rejected attempts as well as successful examples. This is a proposed method, not a claim that these vendors have been tested by this publication.
Costs and unresolved evidence
Do not equate an interactive assistant seat, media credit, billable character, hosted token or self-hosted GPU hour. To estimate actual spending, count accepted results, failed attempts, revision cycles, human review, security operations and export/storage costs. AI 10 must supply dated provider-specific pricing records with tier, unit, currency and region; in their absence, monetary figures and claims of price parity remain unknown. Account-level availability and contract addenda require verification. No universal winner score or fictitious hands-on rating is assigned.
Decision for this scenario
Prefer native-workbook assistants for initial analysis, but publish only explanations with independently checked formulas and source cells.
The article has documented feature and policy evidence but no independent hands-on performance test. Reconfirm plan, region and terms before publication; editorial ready is not WordPress publication approval.
Sources and Further Reading
Original provider and policy sources are listed here. Source-to-claim identifiers are maintained separately in the editorial CSV rather than inserting numbered references into the main text. Where documents are mutable, the access date describes the verification point only.
- Microsoft — Get data insights with Copilot in Excel (checked 2026-10-25)
- Google — Collaborate with Gemini in Google Sheets (checked 2026-10-25)