Gleaner · Keep what’s yours

The tax losses in your
accounts are hiding.
Gleaner finds them.

A free calculator for people with investments spread across brokerages. Drop in the CSV files you already download — see every underwater position, what selling would offset, and the wash-sale traps between your accounts.

Not a habit. A moment.

You don't need Gleaner every month — you need it three or four times a year, when it counts:

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The market just dropped

Red days are harvest days. What fell below what you paid — across every account?

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You just realized a big gain

Sold company stock, property, or a winner? Losses elsewhere can cancel the tax bill — if you find them before Dec 31.

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It's year-end

December is the deadline. Ten minutes with your positions files beats a January surprise.

Three steps. No signup.

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Drop in your CSVs

One file per brokerage — the default positions download, thirty seconds each. Schwab, Fidelity, E*TRADE, and J.P. Morgan are recognized automatically. Most other holdings CSVs work through a one-minute column mapper.

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See what's harvestable

Every position worth less than you paid, ranked by loss — with an estimate of the tax you'd save by offsetting gains you've already realized this year.

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Spot the traps

Symbols held in more than one account get flagged for wash-sale risk — the dividend-reinvestment gotcha most tools never check across brokerages.

Keep what’s yours — your money, and your data.

Gleaner has no server, no database, no accounts, and no tracking. The files you import are parsed locally and stored only in your own browser. We couldn't see your portfolio if we wanted to — there is nothing to breach, nothing to sell, nothing to subpoena. One button erases everything.

Why this exists

After ten years in fintech, I was laid off. My company stock was down 60% from its peak, and my portfolio was scattered across brokerages. Total blind spot.

Then I gathered all my investment details into one place. Hidden inside were tax losses I didn’t even know I had. Selling them wiped out my capital gains tax bill for the year, allowing me to diversify tax-free.

The math was simple. Finding the clarity to see it wasn't.

Every other tool demands your brokerage passwords to give you that clarity. I built the one that doesn't.

Common questions

Is this tax advice?

No. Gleaner is a calculator: it does arithmetic on files you provide and shows you the results. You make the decisions, and anything you plan to act on is worth confirming with a tax professional. Nothing here recommends a trade.

Are capital gains taxed differently from regular income?

Yes, and this surprises almost everyone. Profits on investments held over a year ("long-term") get their own lower schedule: 0%, 15%, or 20% depending on household income, plus a 3.8% surcharge above roughly $250K for married filers. Profits on things held under a year ("short-term") are taxed like your paycheck, at regular income rates. Gleaner's federal dropdown shows the long-term schedule, since that's what harvested losses usually offset.

What if my gains are short-term?

Then harvesting is worth even more than Gleaner estimates. Losses offset gains of the same type first, and short-term gains are taxed at higher rates, so canceling them saves more per dollar. Gleaner uses the long-term schedule for its estimate, which means the number it shows you is the conservative one. The real savings can only be higher.

What's a wash sale?

If you buy the same investment within 30 days before or after selling it at a loss, the IRS disallows the loss. The sneaky part: automatic dividend reinvestment counts as a purchase, in any of your household's accounts. Gleaner flags positions held in more than one account so you can check reinvestment settings before you sell.

What's a tax lot, and why do I care?

Every time you buy (or receive) shares, that batch is a "lot" with its own purchase date and price. One stock can hold winning lots and losing lots at the same time, and you're allowed to sell only the losers. That's often where the biggest hidden losses live, especially in employee stock plans. Gleaner shows lots individually so you can pick exactly which ones go in your plan.

Is my data really private?

Yes, structurally. Gleaner has no server and no database, so there is nowhere for your data to go. Files are read by your own browser and stored only on your device. One button erases everything, and clearing your browser data does the same.

How often should I use this?

A few times a year, when it matters: after a market drop, after selling something big, and before December 31. There's a reminder button in the app that adds a year-end nudge to your own calendar, no email required.

This tool is free.

If it saves you money, tips are lovely 🙂
No paywall, no premium tier, no email capture.

Gleaner is an educational calculator, not investment, tax, or legal advice. It performs arithmetic on data you provide; it does not recommend transactions, and its estimates use simplified assumptions. Tax-loss harvesting involves rules (wash sales, holding periods, basis reporting) with real consequences — confirm your plan with a qualified tax professional before acting. No warranty of any kind.