StackViewer vs Capitally

If you already know what XIRR is, you do not need either of us to explain it — and Capitally is written for exactly that reader. It is a privacy-first, EU-hosted tracker whose whole reason to exist is measuring return correctly: time-weighted return to judge your strategy, money-weighted return (XIRR) to judge your timing, and a clean decomposition of every result into capital gain, dividend income, currency gain, fees and tax. There is no broker linking, no Plaid, no aggregation; you feed it transactions by CSV, paste or manual entry, and in exchange your data never leaves your device unencrypted. That is a coherent, honest design, and for a certain kind of investor it is exactly right.

StackViewer starts from a different question. We assume the return number is table stakes and ask the follow-up: were the decisions behind that number any good? We connect to 31 brokers over read-only OAuth (via SnapTrade), rebuild your positions automatically, and then grade entries and exits, compute the opportunity cost of the trades you actually made versus the ones you planned, and tag every trade with the reason, conviction and emotion you recorded at the time. If Capitally is the measurement instrument, StackViewer is the coaching notebook that plugs into the same wiring. This page is about which one you actually need.

Side by side

Prices and features checked on mycapitally.com/pricing, 9 September 2026. Capitally uses value-based pricing tied to tracked net worth, so the figure you see at checkout may differ; the €80 and €250 anchors are Capitally's own published plan references. Tell us at hello@stackviewer.net if anything here is out of date and we will correct it.

Who each tool is actually for

Where Capitally is the better tool

Three things, plainly. First, the returns maths: Capitally computes XIRR and TWR side by side and decomposes every result into capital gain, dividend, currency, fees and tax for any account, asset or custom slice — that granularity of cash-flow-accurate attribution is deeper than StackViewer offers, and it is the core of their product rather than a feature bolted on. Second, asset breadth and tax: options with Greeks, private equity with TVPI/DPI/RVPI, real estate, collectibles, cash and debt are all treated as first-class assets and flow into multi-jurisdiction tax reporting with tax-loss harvesting and specific-lot cost basis. StackViewer excludes custom and non-broker assets from analytics entirely and offers no tax reporting — you export data for your accountant. Third, privacy: Capitally is end-to-end encrypted on your device with no account aggregation, which for some investors is not a nice-to-have but a hard requirement. If any of those three is your priority, Capitally wins, and we would rather you knew that before you switched than after.

The real difference

Capitally and StackViewer both start from the same maths, but they answer different questions with it. Capitally answers “what did my portfolio return, precisely, after cash-flow timing, currency and tax?” — and it answers it beautifully, on data you have curated and encrypted yourself. StackViewer answers “which of my decisions produced that return, and which ones quietly cost me?” We connect to your brokers automatically so the position data maintains itself, then layer the decision analytics on top: every closed trade gets an entry and exit grade, an opportunity-cost figure against the plan you wrote down, and the reason, conviction and emotion you logged when you opened it. Over a few dozen trades that surfaces patterns a return number never will — that you cut winners early, or that your “high conviction” buys underperform your quiet ones. Capitally is the instrument that measures the outcome; StackViewer is the layer that tells you why the outcome happened. Serious investors often run both, and there is nothing contradictory about that.

Switching from Capitally

There is no file to migrate. Capitally holds your data as an encrypted transaction ledger on your device; StackViewer rebuilds your portfolio from the brokers themselves. You connect each broker once through read-only OAuth (via SnapTrade), we pull your positions and history, and your dashboards populate on the first sync — typically within an hour. Before you leave Capitally, use its export-anything feature to save your full transaction history to CSV or Excel as a local archive; that record is yours to keep regardless of which tool you use. Two honest caveats: StackViewer only ingests what your connected brokers report, so any custom or off-broker assets you tracked in Capitally (property, private equity, collectibles) will not appear in our analytics — and StackViewer does not produce tax documents, so if Capitally was doing your tax reporting, keep it for that. Many people keep both: Capitally for measurement and tax, StackViewer for the decision layer and automatic broker sync.

Frequently asked

Is StackViewer a Capitally alternative?

Partly. If you came to Capitally for cash-flow-accurate XIRR and tax reporting, StackViewer is not a like-for-like swap — Capitally does that maths more deeply and covers asset classes we exclude. StackViewer is an alternative if what you actually want is automatic broker sync plus a decision layer — trade grading, opportunity cost and behavioural tags — sitting on top of the return numbers. See our fuller Capitally alternatives roundup.

Can I move my data from Capitally to StackViewer?

You do not migrate a transaction file. StackViewer connects to your brokers directly through read-only OAuth (via SnapTrade) and rebuilds your positions and history from the source, so there is nothing to export from Capitally first. Capitally lets you export your full transaction history to CSV or Excel at any time if you want a local archive before you switch.

Which is cheaper?

StackViewer has a free-forever plan with no card, so at entry level it is cheaper. Capitally has no free tier — a 14-day trial then paid plans from about €80/year (Navigator) up to €250/year (Captain), as of 9 September 2026. If you need Capitally's tax and options depth, that price buys things StackViewer does not sell at any tier.

Comparison accurate to the best of our knowledge on 9 September 2026, based on publicly available information from mycapitally.com. Product names and trademarks belong to their respective owners; StackViewer is not affiliated with Capitally. Not financial advice.