Twenty-two data prompts for Claude — built for Claude Opus 4.8, with Fable 5's 1M-token context for the biggest files. Attach a CSV or spreadsheet and Claude reads it; turn on the analysis tool so it runs real code for exact numbers, and ask for charts as Artifacts you can preview. Wrap pasted data in XML tags and use extended thinking for inference and forecasting.
Pair these with the best Claude prompts, the cheat sheet, and Claude business prompts for turning findings into decisions.
Explore & understand
Five prompts for a first pass at any dataset. Always start with a data-quality check so dirty data doesn't corrupt the conclusion.
1. First Look at a Dataset
Give me a first look at this dataset. Use the analysis tool to compute, don't estimate.
The question I care about is [question].
<data>
[attach the CSV/Excel, or paste it; describe the columns]
</data>
Do this:
- Data-quality check first: row count, columns and types, missing values, duplicates, obvious anomalies.
- A quick statistical summary of the key columns.
- The 3 things that stand out most.
- What I should ask next given my question.Why it works: Leading with a data-quality check catches missing or dirty data before it skews everything after it.
2. Answer a Specific Question
Answer a specific question from my data. Compute it with code and show your work.
Question: [precise question, e.g. "what was revenue by region in Q2 vs Q1?"].
<data>
[attach or paste the data]
</data>
Do this:
- Give the exact answer with the numbers.
- Show the calculation/logic so I can verify it.
- Note any assumption you made (date ranges, filters, how you handled blanks).
- Flag if the data can't actually answer this.Best for: Getting a trustworthy number — "show your work" lets you check it against a known value.
3. Find the Story in the Numbers
Find the narrative hidden in my data. Think step by step.
Audience for the story: [exec / team / customers].
<data>
[attach or paste the data]
</data>
Do this:
- Surface the 3 most surprising or decision-relevant patterns.
- For each: the finding, the evidence (numbers), and the "so what".
- Note any correlation I'd be wrong to read as causation.
- End with the single headline finding, in one sentence.Why it works: The "so what" and causation caveat turn raw patterns into something you can act on responsibly.
4. Segment and Compare
Break my data into meaningful segments and compare them. Use code for exact figures.
<data>
[attach or paste the data]
</data>
Segment by: [dimension, e.g. plan, region, cohort] and compare on [metric].
Do this:
- Show each segment's key metrics in a table.
- Call out the biggest differences and whether they're likely meaningful.
- Note segments too small to trust.
- Suggest the one segment worth a closer look and why.Best for: Finding where the action is — averages hide the segments that actually differ.
5. Spot Anomalies and Outliers
Find anomalies and outliers in this data. Compute with code.
<data>
[attach or paste the data]
</data>
Context: [what "normal" looks like, if you know].
Do this:
- Identify outliers and unusual patterns, with the rows and values.
- For each, offer the most likely explanations (real signal vs. data error).
- Tell me which to investigate first.
- Don't drop anything silently — list what you flagged.Why it works: Distinguishing "real signal" from "data error" stops you from chasing a typo or ignoring a real spike.
Spreadsheets & formulas
Four prompts for spreadsheet work. Describe your real columns so formulas reference them correctly.
6. Write a Formula and Explain It
Give me a working spreadsheet formula and teach me why it works.
Tool: [Excel / Google Sheets]. My columns: [e.g. dates in A, amount in B, category in C]. I want to [what to calculate].
Do this:
- The exact formula to paste, using real cell references.
- Each part explained in one line.
- A cleaner alternative (pivot table, QUERY, SUMIFS) if there is one.
- Edge cases to watch (blanks, text vs. numbers, ranges).Best for: Formulas that work first try because they use your actual column layout.
7. Debug a Broken Formula
My spreadsheet formula is wrong. Fix it.
Tool: [Excel / Google Sheets].
<formula>
[paste the formula]
</formula>
What it should do: [intent]. What it returns instead: [error or wrong value].
Do this:
- Tell me exactly what's wrong and why.
- Give the corrected formula.
- Point out anything fragile that will break later.Why it works: Intent plus actual output lets Claude find the mistake instead of guessing at what you meant.
8. Turn a Question Into a Pivot Plan
Tell me how to set up a pivot table to answer my question.
Tool: [Excel / Google Sheets]. My data has columns: [list]. I want to see [what].
Do this:
- Exactly what to put in Rows, Columns, Values, and Filters.
- Which aggregation (sum, count, average) and why.
- How to sort or format it to read clearly.
- One follow-up view worth adding.Best for: Skipping the trial-and-error of dragging fields around a pivot builder.
9. Build a Reusable Spreadsheet Model
Help me design a spreadsheet model.
Goal: [what it should calculate, e.g. a simple budget / pricing / forecast model]. Inputs I have: [list]. Outputs I want: [list].
Do this:
- Lay out the tabs/sections and what each holds.
- List the input cells vs. calculated cells.
- Give the key formulas.
- Add checks that warn me if an input looks wrong.
Keep it simple enough that I can maintain it.Why it works: Separating inputs from calculated cells gives you a model you can actually update without breaking it.
Charts & Artifacts
Four prompts for visuals. Ask for an Artifact and name the single point the chart should make.
10. Build the Right Chart as an Artifact
Turn my data into a clean chart as an Artifact.
<data>
[attach or paste the numbers]
</data>
The point I want it to make: [message].
Do this:
- Pick the chart type that best shows that point; say why in one line.
- Render it as an interactive Artifact (self-contained).
- Label axes, add a clear title, format numbers readably.
- Suggest one alternative view of the same data.Best for: A visual you can see and tweak, not a description of one.
11. Small Dashboard From a Dataset
Build a small dashboard as an Artifact from this data.
<data>
[attach or paste the data]
</data>
Audience: [who]. The 3-4 things they care about: [metrics].
Do this:
- A single self-contained HTML Artifact with 3-4 charts + key numbers up top.
- Choose the right chart per metric; keep it clean and readable.
- Add a one-line takeaway under each chart.
- Note any metric the data can't support yet.Why it works: Naming the audience's real priorities keeps the dashboard focused instead of a wall of every possible chart.
12. Critique My Chart
Critique this chart and make it clearer.
<chart>
[attach a screenshot of the chart, or describe/paste it]
</chart>
What I want it to communicate: [message].
Do this:
- Say whether the chart type and design serve that message.
- Flag anything misleading (truncated axes, wrong scale, chart junk).
- Suggest specific fixes, and a better chart type if needed.
- If useful, rebuild the improved version as an Artifact.Best for: Catching misleading or cluttered visuals before they go in a deck.
13. Explain a Chart Someone Sent Me
Explain what this chart is really showing.
<chart>
[attach a screenshot or image of the chart]
</chart>
Do this:
- Tell me the main takeaway in one sentence.
- Point out what the chart is NOT showing that I might assume.
- Flag any way the visual could be misleading.
- List 2 questions I should ask about the underlying data.Why it works: Claude is multimodal, so it reads the actual image — and naming what it doesn't show guards against over-reading it.
Stats & modeling
Four prompts for inference and forecasting. Turn on extended thinking; ask Claude to state assumptions and be honest about uncertainty.
14. Explain a Statistic Plainly
Explain a statistical concept or result in plain language.
Explain [concept or result, e.g. "p-value", "our A/B test's 3% lift with p=0.08"] to [me / my team].
Do this:
- A one-sentence plain-English meaning.
- What it does and does NOT let me conclude.
- One concrete example.
- The mistake people make when interpreting this.Best for: Making sense of a stats output without a textbook — the "does not let me conclude" line prevents overclaiming.
15. Sanity-Check an A/B Test
Sanity-check my experiment. Think step by step.
Setup: [what was tested, metric, variants]. Results:
<results>
[sample sizes, conversions/values per variant]
</results>
Do this:
- Compute the difference and whether it's likely real vs. noise (with reasoning).
- Flag issues: too-small sample, peeking, novelty effect, unequal groups.
- Tell me what I can honestly claim from this.
- What I'd need to be more confident.Why it works: Making Claude reason about sample size and pitfalls first stops a lucky-noise result from shipping as a win.
16. Forecast From History
Make a defensible forecast from my history. Think step by step and compute with code.
<data>
[paste the time series, e.g. monthly revenue]
</data>
Forecast [metric] for [period].
Do this:
- State the trend and any seasonality you detect.
- Give base, optimistic, and conservative projections with the assumptions behind each.
- List what could break the forecast.
- Be explicit that this is an estimate, not a guarantee.Best for: Planning — three scenarios with stated assumptions beat one confident number.
17. Choose the Right Analysis
Help me pick the right way to analyze this. Think step by step.
My question: [what I want to know]. My data: [describe what you have — columns, size, type].
Do this:
- Recommend the analysis/approach that fits, and why.
- Warn me about assumptions it requires and whether my data meets them.
- Suggest a simpler fallback if the ideal approach is overkill.
- Tell me how I'd know the result is trustworthy.Why it works: Picking the method before running it avoids torturing the data with the wrong technique.
Report & communicate
Five prompts to turn analysis into something people act on. Ground every claim in the data.
18. Executive Summary of an Analysis
Write an executive summary of my analysis.
Audience: [exec / board / client]. They have [time] and care about [priority].
<findings>
[paste your findings or the analysis]
</findings>
Do this:
- Lead with the headline finding and the recommended action.
- 3-5 supporting points, each with the number behind it.
- The one risk or caveat they must know.
- Keep it to [length]; no jargon.Best for: Getting a decision — lead with the recommendation, back it with numbers.
19. Data-Backed Recommendation
Turn this analysis into a recommendation. Think step by step.
<findings>
[paste the findings]
</findings>
The decision on the table: [decision].
Do this:
- State a clear recommendation.
- Tie each supporting reason to a specific finding.
- Give the strongest counterargument and why you still recommend it (or don't).
- Note what would change your mind.Why it works: Tying reasons to specific findings — and airing the counterargument — makes the recommendation credible.
20. Clean and Structure Messy Data
Clean this messy data into something usable. Use code where it helps.
<raw>
[paste or attach the raw data]
</raw>
I want it as [target format, e.g. a table with columns X, Y, Z].
Do this:
- Normalize inconsistent formats (dates, casing, units, spelling).
- Flag duplicated or suspect rows instead of silently dropping them.
- Output the clean version I can paste into a spreadsheet.
- List every transformation you applied so I can audit it.Best for: Auditable cleanup — the transformation log means it isn't a black box.
21. Design a KPI or Metric
Help me define a metric that actually reflects what I care about.
What I'm trying to measure: [the real thing]. Data I have access to: [sources].
Do this:
- Propose 2-3 candidate metrics with exact definitions and formulas.
- For each, what it captures and how it could be gamed or misleading.
- Recommend one, plus a guardrail metric to watch alongside it.
- How often to review it.Why it works: Naming how a metric could be gamed keeps you from optimizing a number that doesn't mean what you think.
22. Answer "Why Did This Change?"
Help me understand why a metric moved. Think step by step; compute with code.
Metric: [metric]. It went from [X] to [Y] over [period].
<data>
[attach the relevant data — by segment, over time]
</data>
Do this:
- Decompose the change: which segments/drivers account for how much of it.
- Rank the contributing factors by size.
- Separate what the data shows from what's a hypothesis.
- Tell me the one thing to check next to confirm the cause.Best for: The most common data question at work — decomposing a change into its real drivers.
Save your recurring datasets, definitions, and reporting formats in a Project so Claude keeps them across analyses. For the underlying pattern, see the Claude prompt cheat sheet, and turn findings into decisions with the Claude business prompts.
Frequently Asked Questions
Can Claude actually analyze a CSV or spreadsheet?
Yes. Attach a CSV or Excel file and Claude reads it directly. With the analysis (code-execution) tool enabled, Claude can run real code on your data to compute exact aggregates, clean it, and generate charts, rather than eyeballing the numbers. For big files, that tool matters — it gives you precise results instead of estimates. Always sanity-check the output against a few known values.
Which Claude model is best for data work?
Claude Opus 4.8 is the default for analysis that needs careful reasoning, and Fable 5 handles the largest, most complex datasets with its 1M-token context. Turn on extended thinking for anything involving inference, forecasting, or multi-step logic. Haiku 4.5 is fine for quick lookups and simple formulas.
How do I get exact numbers instead of estimates?
Enable the analysis tool and ask Claude to compute the answer with code rather than estimate it. When it runs code on your uploaded data, the aggregates are exact. Without the tool, a language model can approximate but may miscount on large tables — so for anything that needs to be right, ask it to use code and show its work.
Can Claude build charts and dashboards?
Yes — ask for the chart as an Artifact and Claude renders an interactive visual beside the chat that you can preview and tweak. You can request a specific chart type, a small dashboard of several charts, or a self-contained HTML file you can download. Tell Claude the single point the chart should make so it picks the right visual.
Why start every analysis with a data-quality check?
Because dirty data quietly corrupts conclusions. Asking Claude to first report row count, missing values, duplicates, and obvious anomalies catches problems before they skew the analysis. Several prompts here open with that step for exactly this reason — it's the cheapest way to avoid a confident wrong answer.
How do I stop Claude from inventing numbers?
Give it the real data in a tag or file, ask it to use the analysis tool to compute rather than recall, and tell it to say "the data doesn't show this" instead of guessing. Add "cite the specific rows or figures behind each claim". Grounding every number in your actual data is the best guard against hallucinated statistics.