ChatGPT

Claude vs ChatGPT for Data Analysis

Vendor pages document file and plan constraints for Claude and ChatGPT data analysis, but do not establish which assistant is more accurate.

Sources checked 2 Oct 2026

For data analysis, OpenAI's File Uploads FAQ covers common text, spreadsheet, and data files, while Anthropic's “Upload files to Claude” guide lists CSV and XLSX support and requires code execution plus file creation for XLSX; Chat Picker has not tested either assistant for this use. The vendors' OpenAI pricing page, Claude pricing page, OpenAI accuracy note, and Anthropic accuracy note document plan limits, training controls, and accuracy cautions, but do not establish which assistant will be more accurate or reliable on your data. This claude vs chatgpt comparison therefore covers documented constraints, not a quality ranking.

What the vendors document: Claude vs ChatGPT

As read on October 1, 2026, OpenAI's File Uploads FAQ says each file uploaded to a ChatGPT conversation has a 512MB hard limit. CSV files and spreadsheets are limited to approximately 50MB, depending on row size, and Free users have three uploads per day. At the same reading, Anthropic's upload guide lists 500MB per chat upload and 30MB per project file, with additional token limits based on extracted content. These are stated ceilings, not guarantees that a file at the ceiling will fit within a current plan or account limit.

OpenAI says uploads are available on Free and paid plans, subject to plan-specific limits and account settings. Its ChatGPT pricing page describes Free uploads as limited, Go as offering more messages and uploads, and Plus as providing expanded uploads. Anthropic's Claude pricing page says Free includes web search, file creation, and code execution, while Pro adds more usage and capabilities.

Message capacity is not expressed as one fixed count on either pricing page. OpenAI does not publish exact message counts, while Anthropic says usable capacity varies with conversation length, complexity, model choice, and feature use. Its pricing page also describes usage through a rolling five-hour window, with weekly limits on paid plans.

For data handling, OpenAI lists an opt-out from training on chats for Free, Go, Plus, and Pro. Anthropic lists opt-outs for Free, Pro, and Max, and says Team is not trained on by default. These controls concern model-training use; you still need to check the privacy and workspace settings that apply to your account before uploading sensitive data.

OpenAI says ChatGPT can produce incorrect or misleading outputs and may sound confident when wrong, so its accuracy note tells users to verify important information from reliable sources. Anthropic says Claude can occasionally be incorrect or misleading, warns against relying on it as the only source of truth, and recommends reviewing cited sources and original pages. Neither accuracy note provides a success rate for your particular files or analysis.

What the documentation cannot tell you

The documentation cannot tell you whether either assistant will interpret your schema correctly, preserve edge cases, apply your definition of a metric, or choose an appropriate chart. Nor can it tell you how an account will handle a malformed workbook, a long conversation, a restricted workspace, or an interrupted tool run. Test those points with permitted, de-identified data and required calculations rather than inferring them from feature lists.

Chat Picker's method records vendor-published figures and marks an unconfirmed value “Not verified”; it has no quality, speed, accuracy, reliability, or benchmark results of its own. The earlier version of this page used unsourced statistics and test results, which have been removed.

How to check it yourself

Run each step in a fresh chat, give both assistants the same file and prompt, and record the plan, visible model label, upload status, and whether a tool ran. Using the upload figures read on October 1, 2026 from the linked vendor pages, enter this CSV exactly:

record,vendor,value,qualifier
conversation file,OpenAI,512MB,hard limit
spreadsheet,OpenAI,50MB,approximate
chat upload,Anthropic,500MB,per file
project file,Anthropic,30MB,per file

Parsing and scope. Give both assistants the CSV above and the prompt: “Return a table grouped by vendor. Preserve the phrases ‘hard limit,’ ‘approximate,’ and ‘per file’ exactly; state which upload location each row describes. Show the code used to parse the CSV. Do not rank the vendors.” Look for dropped qualifiers or mixed upload locations. Write down the table, code, and assumptions.
Calculation audit. Give the same file and ask: “Calculate the spread between the largest and smallest documented value within each vendor after expressing both in MB. Keep the approximate spreadsheet limit labeled as approximate, show each formula, and state any comparability caveat.” Check whether intermediate steps are visible. Record every formula, unit conversion, and caveat.
Chart design. Ask: “Create two separate bar charts, one per vendor. Label the unit MB, place the qualifier beside every value, and explain why the panels should not be merged without a caveat.” Look for readable labels and visible uncertainty. Save the chart and note any omitted qualifier.
Source audit. Give the same CSV and the two linked upload pages, then ask: “Attach a source to every row. State the page title, vendor, the limit’s exact scope, and October 1, 2026 as the date read. Separate documented facts from interpretation, and identify anything the pages do not settle.” Record each citation and any unsupported statement.

These are test instructions, not reported results.

Which rows of the comparison matter

In the Claude vs ChatGPT comparison matrix, check these rows:

Free plan, Low-cost tier, Main paid plan, and Heavy-use plans for feature and price differences.
How usage limits are described for upload, tool, and capacity terms.
Training on your chats for the published training control.
Context window in the app if your files or conversations may be long.
Team plan if more than one person will work with the data.
Ads if you are considering ChatGPT Go.

Each matrix figure carries its vendor source and read date, while an unconfirmed cell is marked “Not verified” and left blank. Check the linked vendor upload pages as well: a plan name alone does not establish whether a particular file will be accepted.