What the review reads, and what it cannot
A filed Form 1040 runs to well over a hundred boxes, and on most returns nearly all of them are zero. Nine carry the story. This is which nine, what gets built out of them, and the questions they can and cannot settle.
The nine lines
Taken from Form 1040 for tax year 2024, with the labels as the form prints them.
- Line 1z — wages, salaries and tips (“Add lines 1a through 1h”)
- Line 2b — taxable interest
- Line 11 — adjusted gross income
- Line 12 — standard deduction or itemized deductions
- Line 15 — taxable income
- Line 21 — total credits (“Add lines 19 and 20”)
- Line 24 — total tax
- Line 25d — federal income tax withheld
- Line 35a — the refund claimed
Those line numbers are specific to 2024. The IRS renumbered Form 1040 for tax year 2025 — adjusted gross income moved to line 11a and the deduction to line 12e — so a 2025 return will not line up, and the text extractor will mis-read it. Supporting 2025 is one of the things still to be built.
What gets built out of them
Four identities, displayed rather than solved. The review does not recompute your tax and has no opinion on whether the figures on the return are right:
- Your effective rate — total tax over adjusted gross income. Almost always lower than the bracket people quote, because a bracket is the rate on the last dollar only.
- Where the money narrowed — income, then taxable income, then tax, each drawn as a share of adjusted gross income. The deduction is the visible gap between the first two.
- Where your payments went — withholding and credits split into the part kept as tax and the part coming back. When the return owes instead, it splits the tax into what was covered and what is still due.
The three questions
Always the same three, worded from whatever figures are present, each citing the line it came from.
Cash flow — lines 24, 25d and 35a
Whether you overpaid or underpaid across the year. A large refund is not a win; it is money that sat with the IRS instead of in your pay packet. This is a cash-flow observation and not a tax saving — the tax is the same either way.
Deduction — line 12
Which deduction you took, against the standard deduction for your filing status. For 2024 that was $14,600 single and married filing separately, $29,200 married filing jointly and qualifying surviving spouse, and $21,900 head of household, with additions for age 65 and blindness.
Credits — lines 19 to 21
What was claimed, and the categories most often missed. An empty line 21 is not evidence that nothing was available — only that nothing was claimed.
What it cannot establish
Worth being blunt about, because these are the limits that matter:
- It cannot tell you that you qualify for anything. Eligibility for every credit and most deductions turns on facts that never appear on Form 1040.
- It cannot see the documents behind the return — no W-2s, no 1099s, no Schedule A, no schedules at all. It reads the summary lines and nothing under them.
- It does not check the return for errors or recompute the liability. If a figure on the return is wrong, everything downstream of it here is wrong too.
- Reading a PDF is imperfect. It misses amounts and can pick up the wrong ones, which is why the preview shows every extracted figure in an editable field and asks you to check each one. Scanned returns have no selectable text and produce nothing at all.
- It is not tax advice, and nothing it says should drive a filing decision on its own.
To be built
Tax year 2025 support, more than the nine summary lines, and the schedules behind them. If there is a line you keep wanting it to read, that is useful to know.
Try it on the sample
A complete 2024 single-filer return is built in, so you can see exactly what the review produces before putting your own figures anywhere.