Get straight to work.
A ribbon, formula bar, sheet tabs and familiar keyboard shortcuts. Spend your time on the workbook.
Kallisto Cella
Download for Windows
A fresh perspective on spreadsheets
Every cell.
Endless
possibilities.
Your budget. Your business. Your next big idea. Plan, calculate and see the bigger picture in one beautifully familiar spreadsheet workspace.
Windows 10 / 11 · 64-bit · Alpha testing build
Native desktopXLSX & CSVOpen source
REAL APP. REAL WORKBOOK.Emerald workspace
Construction BOQ · example workbookExplore the BOQ example
01Calculate with confidence
02Turn numbers into a story
03Keep your workflow yours
MORE THAN ROWS AND COLUMNS
A familiar workspace.
A fresh perspective.
The tools you reach for, together in a focused native spreadsheet. Start with a blank sheet, open an existing workbook or build on an example.
Make your numbers speak.
Formulas, tables, conditional formatting and charts turn a busy sheet into a useful view of your project.
Work with your files.
Open and save XLSX workbooks, import or export CSV, and work locally on your desktop.
BUILT FOR THE WORK IN FRONT OF YOU
Small details.
More possibilities.
A practical set of spreadsheet tools for budgets, estimates, schedules and the everyday work between them.
Formulas that go further
Calculate with a broad function library, dynamic arrays and named expressions with LET and LAMBDA.
CalculateA clear view of the numbers
Explore trends with charts, summarise data with PivotTables, and make patterns stand out with conditional formatting.
VisualiseStructure that stays useful
Organise with tables, sort and filter, add data validation, and leave cell comments for your next review.
OrganiseReady for your tools
Use the command line, MCP server or control channel to connect external agents and automate workbook operations.
AutomateONE WORKSPACE. YOUR POSSIBILITIES.
For the plans you make.
And the questions you ask.
A monthly budget, a business review or your next assignment. Start with the numbers that matter to you and build a clearer view.
Actual app screenshot 01 PERSONAL & PROJECT BUDGETING
Make room for your plans.
Organise income and expenses, calculate totals and compare planned amounts with what you spend. Keep the details together in a workbook you can revisit.
FormulasNumber formatsCharts
Actual app screenshot 02 SALES & BUSINESS DASHBOARDS
See the story in your sales.
Bring a sales table into focus with totals, conditional formatting and charts. Sort and filter the details, then compare performance from one view.
TablesSort & filterCharts
Actual app screenshot 03 STUDY & DATA ANALYSIS
Turn data into understanding.
Organise results, calculate averages and highlight patterns. Work through a gradebook, compare study data or open a CSV to start exploring your own questions.
FunctionsFormattingXLSX & CSV
Working on a construction project? Explore a detailed bill of quantities and its linked cost charts.
See the BOQ exampleFROM THE FIRST QUANTITY TO THE FINAL FIGURE
Built for the way
you build.
Put your bill of quantities in perspective. List the work, enter quantities and rates, then see how each package contributes to the estimate.
Download the BOQ workbookTHE EXAMPLE PROJECT
A clearer cost conversation.
Explore Aster Courtyard Residence, an illustrative BOQ in Indian rupees. Follow the estimate from individual line items to a visual cost breakdown, then change a quantity or rate to explore your own scenario.
- 1Enter the work
Descriptions, units, quantities and rates.
- 2Let formulas do the maths
Line amounts and category totals in one file.
- 3See where the budget goes
Compare work packages with linked charts.
All quantities, rates, contingency and tax assumptions are illustrative. This is an editable example, not a market estimate or tax advice.
ASTER COURTYARD RESIDENCE
Where the budget goes
Direct works · INR₹62.29L₹62,28,500
Earthwork4.6%
Concrete works45.4%
Masonry13.9%
Finishes22.5%
Services13.6%
YOUR FILES. YOUR FLOW.
From a quick calculation
to a connected workflow.
Keep it simple at the desktop, or connect your own tools when the work calls for more.
Start with what you have
Open an XLSX file or bring in CSV data. Keep familiar formats at the centre of your workflow.
Move at your own pace
Use the desktop interface and keyboard shortcuts, with undo and redo as you refine your workbook.
Connect an external agent
CLI and MCP interfaces expose workbook commands for your own automation and agent setup.
MEET YOUR NEXT WORKSPACE
Your next workbook
starts here.
Install Kallisto Cella, open a sample or your own workbook, and make it your own.
Download for WindowsThis unsigned alpha is intended for testing and Windows may show a publisher warning. Test with copies of your workbooks and check the results with your own files.
View release details & SHA-256A FEW THINGS TO KNOW
Before you
open your first cell.
Getting started, file formats
and the current testing build.
What can I use Kallisto Cella for?
Personal and project budgets, sales dashboards, study and gradebooks, data analysis, construction bills of quantities and everyday calculations. Explore the sample workflows, start with a blank workbook or open your own XLSX or CSV file.
Can I use my existing spreadsheets?
Kallisto Cella opens and saves XLSX workbooks and supports CSV import and export. Compatibility is still being developed, so check the results with your own files and keep backups during testing.
How do I install the Windows build?
Download the installer on a 64-bit Windows 10 or Windows 11 PC and run it. This is an unsigned testing build; Windows may ask you to confirm the publisher. Release details and a SHA-256 checksum are linked beside the download.
Is there a built-in AI assistant or cloud collaboration?
The app has CLI, MCP and control-channel interfaces for external agents and automation. This download does not include a built-in AI chat or a hosted real-time collaboration service.
Is Kallisto Cella open source?
Yes. Kallisto Cella is published by Kallisto Innovation under the MIT or Apache-2.0 software license. The download includes the licenses and component notices; product branding has separate terms. Read the licenses and product notices.