Sumio vs a Spreadsheet for Net Worth and Portfolio Tracking
A spreadsheet is free, completely flexible, and will still open in twenty years. Its main weakness is manual upkeep: every share price and exchange rate you enter goes stale immediately. Sumio updates prices and currencies automatically across more than 50 markets, stores data locally on your device, and charges a subscription above its five-asset free tier. Which option suits you depends on how many positions you hold, how many currencies you deal in, and how often you look at them.
What a spreadsheet does well
People track wealth in spreadsheets because spreadsheets give you complete control. You do not need to wait for a developer to build a feature or ask permission to organize your numbers.
If you keep your personal balance sheet in Google Sheets or Microsoft Excel, you enjoy several clear advantages:
- Zero software subscription cost: Google Sheets is free with any Google account. Excel is included with many corporate or personal Microsoft accounts, and open alternatives like LibreOffice cost nothing.
- Complete mathematical flexibility: You can write any formula. If you want to compute custom tax liabilities, simulate mortgage payoff schedules, or model three retirement income tiers, you can build exactly that.
- No account or third-party sign-up: An offline Excel file does not require creating an account, confirming an email address, or accepting terms from an app maker.
- Long-term file durability: An .xlsx or .ods file is an open standard. The workbook you save to your hard drive today will still open reliably twenty years from now, regardless of what happens to any tech startup.
- Easy collaboration with professionals: When filing taxes or meeting a financial planner, you can email an Excel workbook or grant read access to a Google Sheet in seconds.
- Offline reliability: A local file stored on your computer does not depend on cloud uptime, server status, or network availability.
Where spreadsheets get hard
The friction starts when your balance sheet expands beyond a single bank account and a home. Maintaining an investment spreadsheet over several years exposes common mechanical problems:
1. Manual prices go stale immediately
When you type the price of a stock, ETF, or cryptocurrency into a spreadsheet cell, that figure is static. By the next morning, market movements have made the number inaccurate. If you do not update it before checking your net worth, your totals reflect old data. We covered this dynamic in detail in our guide on keeping a net worth spreadsheet up to date.
2. Foreign currencies require constant maintenance
Holding assets in multiple currencies adds a second layer of manual upkeep. If you earn in euros, hold US-listed index funds in dollars, and own real estate in Czech koruna, every balance sheet calculation requires fresh foreign exchange rates. Without automated currency conversion, a currency shift can look like an investment gain or loss.
3. GOOGLEFINANCE has documented restrictions
Many investors turn to Google Sheets' built-in GOOGLEFINANCE formula. While helpful for simple US portfolios, Google's official documentation outlines clear limitations:
- Quotes may be delayed up to 20 minutes.
- The function does not support most international exchanges outside the United States.
- Google specifies that data is not provided for trading purposes or investment advice.
- Historical quotes cannot be retrieved through the Google Sheets API or Apps Script.
4. Excel Stocks data types require paid subscriptions
Microsoft Excel offers stock and currency data types, but they require an active Microsoft 365 subscription. Market coverage focuses heavily on major western exchanges, and automatic background refresh can fail depending on account licensing and regional settings.
5. Tracking history requires manual monthly snapshots
A spreadsheet calculates your balance sheet as it stands right now. To see how your wealth developed over three years, you have to remember to copy values at the end of each month and paste them into a separate historical records tab. Miss two months, and your historical trend has gaps.
6. Formulas break silently and mobile editing is awkward
Inserting a new row, moving a column, or copying a purchase line can break formula ranges without displaying an error. Furthermore, trying to review a 12-column spreadsheet on a smartphone screen while standing in a store or traveling is clumsy.
Where a spreadsheet is better than Sumio
We build Sumio, but we also use spreadsheets. If a software company tells you their tool is better than a spreadsheet at everything, they are selling rather than explaining.
Here are genuine reasons you might prefer to stick with a spreadsheet:
- A spreadsheet is completely free: Sumio has a free tier that allows up to 5 assets and unlimited liabilities. If you have more than 5 assets, Sumio requires a paid Premium subscription. A spreadsheet has no position limits and no recurring fees.
- Unlimited formula flexibility: Sumio gives you predefined balance sheet categories, custom categories, and custom indicators, but you cannot write custom mathematical formulas. If you want to compute custom capital gains tax brackets, model early retirement safe withdrawal rates, or forecast cash flow based on salary increments, a spreadsheet is far superior.
- Open, universal file ownership: You own an .xlsx or .ods file completely. While Sumio allows you to export all your recorded data, the export file is in JSON format. JSON is standard for software backups and migrating devices, but you cannot open it directly in Excel or Google Sheets without a multi-step data import conversion step (such as Excel Power Query).
- Holdings are still entered manually in Sumio: Sumio does not currently sync with banks or brokers. You still enter your stock symbols, quantities, and dates yourself, or import them via our Excel template. If you dislike entering holdings, Sumio will not eliminate that step today.
- Offline data isolation when using AI: An offline spreadsheet on your computer never communicates with an external server. Sumio stores your records locally on your device with 256-bit AES encryption by default. However, when you run an analysis with Sumio's AI Assistant, the specific figures needed to answer your question are sent to an external AI model provider.
What Sumio does differently
Sumio is designed to solve the single problem that makes spreadsheets frustrating over time: keeping market values, foreign exchange rates, and balance sheet history up to date without linking bank credentials.
Automatic market updates
Sumio retrieves price data for stocks, ETFs, mutual funds, cryptocurrencies, and precious metals from more than 50 global exchanges. You record your quantities once; prices update in the background.
Over 100 currencies converted
Hold assets in USD, EUR, GBP, CZK, or dozens of other currencies. Sumio converts each holding into your selected base currency automatically using current exchange rates.
Automatic history and allocation
Your balance sheet records over time. You can see historical net worth trajectories, asset allocation breakdowns, and total liabilities without copying and pasting monthly snapshot rows.
Private by design on mobile
Data stays encrypted on your device with 256-bit AES. You do not need to register an account or share your email address. Security Lock supports Face ID, Touch ID, and passcodes.
Side-by-side comparison
A factual breakdown of Google Sheets, Microsoft Excel, and Sumio for wealth tracking.
| Feature | Google Sheets | Microsoft Excel | Sumio |
|---|---|---|---|
| Base price | Free with a Google account | Free (web/desktop file) or Microsoft 365 subscription | Free tier up to 5 assets; paid subscription for unlimited assets |
| Initial setup | Manual. You build the tabs, formulas, and data structures yourself | Manual. You write the balance sheet model and calculations | Ready in minutes. Predefined balance sheet and holding records |
| Live price updates | GOOGLEFINANCE formula (delayed up to 20 minutes, mainly US exchanges) | Stocks data type (requires Microsoft 365, limited international coverage) | Automatic background price updates across 50+ global exchanges |
| Multi-currency conversion | Requires GOOGLEFINANCE("CURRENCY:XYZ") formulas across every foreign row | Requires linked currency data types or manual exchange rate tables | Automatic conversion of >100 currencies to your base currency |
| Historical net worth tracking | Manual. You copy and paste static values into an archive sheet each month | Manual. You create snapshot rows or write VBA macros to record history | Automatic. Balance sheet history and asset trajectories record over time |
| Formula flexibility | Complete. Write any custom formula, simulation, or cash flow model | Complete. Full access to complex mathematical models and pivot tables | Structured. Custom categories and indicators, but no arbitrary formula code |
| Phone usability | Clunky. Scrolling wide tables and typing numbers on a small screen is slow | Clunky. Mobile app makes viewing multi-column worksheets difficult | Native mobile app for iOS and Android, plus iPad, Mac, and Apple Vision Pro |
| Where data lives | Stored on Google cloud servers under your Google account | Local computer drive (offline) or Microsoft OneDrive cloud | On your device by default, encrypted with 256-bit AES; optional cloud sync |
| Data export format | Open spreadsheet files (.xlsx, .csv, .ods, .pdf) | Open spreadsheet files (.xlsx, .csv, .ods, .pdf) | Full JSON backup export file (requires conversion step for spreadsheets) |
| Sharing with advisers | Share link with an accountant, financial planner, or partner directly | Email the spreadsheet file directly to your accountant | Personal device app; share reports or export JSON data |
| AI balance sheet analysis | Requires third-party add-ons or copying figures manually into an LLM | Requires Microsoft Copilot subscription add-on | 62 built-in prompts evaluating allocation, debt, and holdings on demand |
Which tool fits your situation?
Keep your spreadsheet if:
- You hold three or four broad index funds in one currency and check them once a quarter.
- You have custom mathematical models for tax optimization, safe withdrawal rates, or business cash flow.
- You want zero ongoing software subscriptions.
- You want to collaborate directly with an accountant or spouse inside a shared online document.
- You prefer reviewing numbers on a full desktop screen rather than a smartphone.
Sumio is worth trying if:
- You hold positions across multiple exchanges, currencies, or asset classes (stocks, ETFs, crypto, precious metals).
- You are tired of maintaining broken formulas and copying fresh share prices and exchange rates manually.
- You want to check your total net worth and asset allocation quickly on your phone or tablet.
- You want automated historical snapshots without maintaining a separate archive tab.
- You want biometric protection (Face ID or Touch ID) protecting your private net worth figures.
Moving from a spreadsheet to Sumio
If you decide to test Sumio, you do not have to type every stock purchase from scratch on your phone. You can import your holdings directly using an Excel file.
1. The four-column template
Sumio's importer reads an .xlsx workbook with a single sheet containing exactly four columns in the header row:
Download the official template: Sumio_Portfolio_Import_XLSX_Template.xlsx
2. Rules for the file
- One row per purchase: If you bought shares in the same company or ETF across three different months, create three separate rows.
- Optional exchange and date: The
exchangeandpurchase_datecolumns may be left blank if unknown, and filled in later inside the app. - Broker statement import: If you download a statement from your broker as an .xlsx file, you can trim away extra columns (such as commission or cash balances) and arrange the remaining data under those four headers.
- File format requirement: The file must be saved in .xlsx format. Sumio does not accept CSV files for portfolio import.
- Scope of import: The template imports stocks, ETFs, and mutual funds. Sumio uses the
purchase_dateto calculate your purchase cost basis and historical performance. Other assets (cash balances, crypto holdings, real estate, and loans) are added directly in the app.
3. Uploading to your mobile device
Save the completed .xlsx file to a location your phone can access (iCloud Drive on iOS or Google Drive on Android). Open Sumio, tap Import, and select the file. Once imported, all holdings appear in your portfolio, and you can edit quantities, purchase dates, or assign custom categories at any time.
4. What happens if you leave Sumio later?
You are never locked into the app. Sumio lets you export your complete financial records as a JSON file at any time. Keep in mind that JSON is a structured data format for backups and migrations; opening it in Excel requires using Power Query (via Data > Get Data > From JSON).
Frequently asked questions
Can I keep my spreadsheet and use Sumio at the same time?
Yes. Many people use Sumio as their day-to-day portfolio tracker on mobile because prices and exchange rates update automatically, while keeping an annual spreadsheet on their laptop for long-term tax planning and custom balance sheet projections.
Does Sumio link to my bank or broker accounts?
Sumio does not currently sync with banks or brokers. You enter holdings yourself or import them via the Excel template. This ensures you never have to provide bank login credentials or share passwords. Direct broker sync is planned for future releases.
What is included in the free tier?
The free tier lets you track up to 5 assets and unlimited liabilities, with access to global market data and predefined categories. The paid Premium tier adds unlimited assets, AI Assistant analysis, custom categories and indicators, and multi-device backup.
Related resources
Explore more tools and guides for structuring your personal balance sheet:
- Free Net Worth Calculator – Calculate your assets, liabilities, and debt ratios privately in your browser.
- The Personal Balance Sheet Guide – Learn how to classify assets and liabilities systematically.
- 62 Free AI Financial Prompts – Copy pre-tested questions for evaluating portfolio risk and diversification in ChatGPT or Claude.
Track your net worth and investments privately
Sumio tracks your net worth, investments, and debts privately on your phone, with automatic price updates across 50+ markets and 100+ currencies. The free tier includes up to 5 assets and unlimited liabilities.
This is general information, not financial or legal advice. Sumio is made by Fiduciary s.r.o., a software company, not an adviser or broker.