A fixed point to measure from
See what you own. Find what it’s worth.
Datum reads your holdings and the filings behind them — so you can decide on data, not narrative.
$8 a month, or $80 a year. Seven-day free trial — cancel before it ends and you won’t be charged.
Illustrative figures. Not a real portfolio.
Where the numbers come from
Built on primary sources, rebuilt nightly.
Datum doesn’t repackage someone else’s dashboard. It assembles its own dataset from the documents companies and funds are required to file, and from official economic series — then refreshes the whole thing every night.
Company filings
Fundamentals, insider activity and institutional ownership read from the disclosures issuers file — not from a summary of them.
Fund disclosures
Holdings, expense ratios and asset mix taken from the periodic reports funds publish themselves.
Official economic series
Rates and macroeconomic series taken from the agencies that publish them.
Traceable by design
Every figure points back to the document it came from. A missing input shows a dash — never an assumption.
What you get
Everything that follows from knowing what you hold.
Portfolio tracking
Link your brokerages or track by hand — every holding in one place, valued daily.
True performance
Time- and money-weighted returns on your linked accounts, against a benchmark you choose.
Exposure X-Ray
See through your funds to real sector, geography and single-stock exposure — including what two funds share.
Fee analysis
The weighted expense ratio you actually pay, converted into dollars per year.
Screeners
Rank companies on published metrics — including a Magic Formula screen — and filter the fund universe on cost, size, risk and returns.
Watchlist and alerts
Follow what you care about, track dividend income, and get told when something you set a threshold on moves.
How it works
Three steps, then it runs itself.
Link your accounts
Connect your brokerage accounts securely, or enter positions by hand. Both end up in the same picture.
Datum rebuilds the data
Every night it refreshes prices, fundamentals, filings and fund holdings across your universe — from the sources, not a cache of a cache.
Read your position
Open the app to valuation, real returns, look-through exposure and fees — already computed, ready to argue with.
Exposure X-Ray
Two funds, one bet.
A portfolio can look diversified and still be concentrated. X-Ray looks through every fund you hold to its underlying positions, then re-adds your real exposure by sector, geography and individual company — including the overlap two funds share without mentioning it.
Fee analysis
The number that never appears on a statement.
Expense ratios are charged quietly, as a fraction of assets, and they compound against you. Datum weights each fund’s published ratio by what you actually hold and converts it into dollars a year — so switching to a cheaper equivalent becomes a comparison instead of a guess.
Cheapest equivalent exposure would run 0.07% — about $499 a year less.
Fund rating
A rating you can check.
Every fund gets one to five stars from the two things that can actually be measured: risk-adjusted return and cost. The formula is published on the rating itself, so you can disagree with it on the merits.
Score = 0.7 × Sharpe percentile + 0.3 × (1 − expense percentile)
Rating = 1–5 stars by score
Higher Sharpe percentile is better. Lower expense percentile is cheaper.
Pricing
One plan. Everything portfolio.
Subscribe to track your accounts, measure real returns, and see through your funds. Start with a seven-day free trial — cancel any time before it ends and you won’t be charged.
Billed annually — about $6.67 a month.
Or $8 a month, billed monthly. Annual is two months free.
- Link unlimited brokerage accounts
- Daily portfolio valuation and true performance (TWR + MWR)
- Full X-Ray: sector, geography and single-stock exposure
- Fee analysis — what your funds really cost per year
- Benchmarks, income tracking and fund overlap
Cancel anytime. Prices shown before any applicable tax.
Questions
Before you hand over your holdings.
Does Datum get my brokerage password?
No. You authorize the connection with your brokerage through a specialist connection provider, and Datum receives read-only access to your positions and transactions. It cannot place trades, move money, or change anything in your account.
Which brokerages can I link?
You get a searchable list of supported institutions when you add an account, covering the large US brokerages. If yours isn’t there, you can enter positions by hand and still get valuation, exposure and fee analysis.
How much history do I get?
Datum values your portfolio from the day you link forward, and imports whatever transaction history your brokerage chooses to share — which varies a lot by institution. Some go back years; some share nothing before the day you connect. Positions held before that show up, but without a purchase date.
Do you sell my data?
No. Your holdings are not sold, shared for marketing, or used to target advertising. There is no advertising on Datum.
Is this investment advice?
No. Datum is a measurement tool. It shows you what you hold, what it’s worth, what it costs and what it’s exposed to. It does not tell you what to buy, and nothing in it is a recommendation.
Is there a free tier?
No — there is one plan, and a seven-day free trial to decide with. Cancel before the trial ends and you won’t be charged.
Can I cancel, and can I leave with my data?
Cancel any time from settings. Unlinking a brokerage revokes Datum’s access to it immediately. And you can export everything Datum holds about you as a single file, or delete your account outright — neither is behind the subscription, so a lapsed or canceled account can still take its data and go.
Start measuring
Start with what you actually own.
Seven days free. $8 a month or $80 a year after that.