Dynamic Spreadsheets with Modern Excel
Stop wrestling with broken cell references and fragile nested formulas. Learn how to combine dynamic arrays, structured references, and resilient lookup logic to build spreadsheets that update automatically and never break when new data arrives.
Like Duolingo, but for Dynamic Spreadsheets with Modern Excel. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.
A short one: 12 levels across 2 sections, about 24 minutes end to end, roughly 5 days at five minutes a day. It moves through Modern Formula Mechanics and Structuring Data for Automation. It assumes you already know the basics.
Free forever · No credit card · iPhone & Android
Key ideas in Dynamic Spreadsheets with Modern Excel
- VLOOKUP uses a static index number that does not update when table columns shift
- XLOOKUP selects lookup and return arrays as separate cell ranges that adjust automatically
- XLOOKUP includes a built-in if_not_found fourth argument to handle missing matches
- Using native fallbacks prevents IFERROR from masking unrelated formula syntax errors
- The inner XLOOKUP evaluates a column header and returns a single dynamic column array
- The outer XLOOKUP searches row headers and uses the inner XLOOKUP as its return array
- Setting match_mode to -1 or 1 instructs XLOOKUP to find exact matches or the next boundary
- Unlike VLOOKUP's true approximate search, XLOOKUP does not require sorted reference data
- XLOOKUP's sixth argument, search_mode, accepts -1 to conduct a reverse bottom-to-top scan
- Bottom-to-top scanning retrieves the most recent chronological entry in an append-only log
- Dynamic array formulas automatically populate neighboring cells down and right from one entry
- If any cell in the intended output area already holds data, Excel returns a #SPILL! error
- Modern Excel spills array results natively without pressing Ctrl+Shift+Enter or dragging fill handles
- Standard AND functions aggregate entire arrays into a single TRUE or FALSE instead of checking row by row
- Multiplying two condition arrays with * treats TRUE as 1 and FALSE as 0, yielding 1 only when both match
- Excel needs parentheses around each comparison so evaluation order processes before multiplication
You've tried the other tabs
Thirty open tabs. Four facts you actually kept.
You watched. You nodded. By Sunday it was gone.
One answer, then back to scrolling.
Eight weeks. You meant to finish. You didn't.
Tomo gives Dynamic Spreadsheets with Modern Excel the Duolingo treatment: levels, streaks, and quick quizzes that test what you just learned. That game loop is what the tabs above never had, so it's the one you actually finish.
Here's what playing it feels like
A real question from this course. Take your best guess.
Why does an XLOOKUP formula stay intact when someone inserts a new column in your worksheet?
Get it right to open this lesson and 11 more in the app.
Where Dynamic Spreadsheets with Modern Excel takes you
- 1
Modern Formula Mechanics
- Upgrading Lookups with XLOOKUP
- Multi-Condition Filtering and Array Logic
- 2
Structuring Data for Automation
- Structured References and Spill Architecture
- Pivot Summaries and Analytical Layouts
2 sections · 4 units · 12 levels. Built to play, not to enroll.
Tomo is in ChatGPT
Tomo is also a ChatGPT plugin: the same playable courses, built and played inside your chat.
Add Tomo to ChatGPT- What to ask
- “Make me a Tomo course on black holes.” “Turn this chat into a Tomo course.”
- What you get
- Quick questions with instant feedback, hearts and stars, ready to play in about a minute.
- Where it goes
- No sign-up to start. Connect your Tomo account and your streak carries on in the app.
You pick the voice
Dynamic Spreadsheets with Modern Excel is taught in the Professor style: clear, structured, thorough. Want a different feel? In the app you can spin up the same topic in any of Tomo's teaching styles. Same facts, totally different vibe.
More Technology on Tomo
Dynamic Excel Workflows
Upgrade from fragile cell formulas to resilient, modern spreadsheet design. Learn how to leverage dynamic arrays, flexible lookups, and structured tables to build spreadsheets that never break when data updates.
Resilient Excel Spreadsheets
Upgrade from fragile, manual spreadsheets to modern, dynamic workbooks. Learn to replace nested IFs, retire brittle lookups with XLOOKUP, and build self-updating models using dynamic arrays and structured tables.
Modern Excel Workflows
Transform brittle, static spreadsheets into resilient, self-updating data models. Master dynamic arrays, structured table logic, and bulletproof lookups to build workbooks that never break when data changes.
Working with Excel Data
Move beyond basic cell entries and static sums to build reliable, adaptable spreadsheets. Learn how to combine dynamic lookup formulas, clean irregular inputs, summarize multi-dimensional tables, and troubleshoot complex calculation models.
Data Analysis from Excel to SQL
Transform messy raw spreadsheets into automated models, interactive dashboards, and robust database queries. Learn to clean data in Power Query, calculate metrics in DAX, and extract answers with SQL.
Excel for Everyday Work
Build confidence in Excel by learning how spreadsheets actually think and operate. From basic data entry and rock-solid formulas to lookups and pivot tables, you'll gain the practical skills needed to organize, calculate, and present data with clarity.
Start Dynamic Spreadsheets with Modern Excel today.
Download Tomo, search Dynamic Spreadsheets with Modern Excel, and play your first lesson in under a minute.