Calculate US taxes from 1099s and brokerage statements
A poster saw a GPT Agent handle tax work and built a case study where ChatGPT accurately computed US taxes from 1099s, a self-employed spreadsheet and brokerage statements.
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- What they did
- A commenter said they built a ChatGPT case study for individual US taxes by feeding it 1099s, a spreadsheet for a self-employed business, and brokerage statements. They spent about an hour tweaking the setup until the calculations were right, then had ChatGPT compare its output to a PBC package and flag issues; the person was the one iterating and checking results.
- How it went
- They said the tax calculation was spot on after about an hour of tweaking, and ChatGPT also identified basic tax-planning ideas correctly. The thread also reflects the obvious limitation: people still warned that tax work needs careful human review because LLMs can make errors.
- Worth knowing
- Expect a couple of hours end to end, with about an hour spent tuning prompts or inputs before the result matched.
Try it yourself with ChatGPT Agent
I am a US taxpayer for tax year [year] with filing status [status]. I will upload my 1099s, my self-employment income and expense spreadsheet, and my brokerage statements. Calculate my federal tax estimate, showing income by source, deductions, self-employment tax, and capital gains, and flag any numbers that look inconsistent or missing. Finished means a clear summary table with your assumptions listed, and I will verify it with a tax professional before filing. Do not submit or file anything.
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Source: Reddit · Undated
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