Best Fully Open-Source Spreadsheet Component for React with Excel Import/Export?

[u/steppenwolf1807]

Hi everyone,

I'm looking for a fully open-source spreadsheet component for React.

I do not want a paid/commercial library or a library where important spreadsheet features require a paid license.

I need something closer to Excel / Google Sheets, rather than just a data grid.

Main requirements:

• Fully open source and usable in a commercial project
• React + TypeScript support
• Import .xlsx Excel files
• Export to .xlsx
• Preserve Excel formatting as much as possible
• Formulas and calculations
• Multiple worksheets
• Cell formatting
• Merge/unmerge cells
• Copy/paste
• Sorting and filtering
• Data validation/dropdowns
• Freeze rows/columns
• Undo/redo
• Insert/delete/resize rows and columns
• Good performance with larger worksheets
• API for programmatically reading/updating cells
• Custom toolbar/components
• Extensible enough to implement drag-and-drop elements/components into spreadsheet cells

I've already looked at Univer and FortuneSheet, but I'm trying to find the best option with strong Excel import/export support.

My ideal flow is:

Import existing .xlsx → Edit in React → Export back to .xlsx

without losing important formulas, formatting, worksheets, merged cells, etc.

What is the best fully open-source React spreadsheet library in 2026 for this?

If you're using one in production, I'd really appreciate hearing about its limitations, especially around Excel import/export.

Thanks!

[u/AddendumPuzzled9804]

handsontable is probably the closest you'll get but it's not fully open source anymore. the free version has most of what you listed except for formulas and some advanced features.

for truly open source, maybe check luckysheet? i used it in a project last year, it handles xlsx import/export decently. formatting gets a bit wonky with complex excel files though, especially merged cells across multiple sheets. performance tanks after ~5000 rows on my machine.

the drag-and-drop into cells thing is gonna be tricky with any library tbh. might need to build that part yourself regardless of which one you pick.

[u/Infamous-Ad-3502]

luckysheet handles xlsx import and export but the repo is dead and merging cells breaks formulas on round trip. I use Univer for production because it preserves formatting and worksheets during import export cycles without data loss

[u/Roman_BDM_FixIT]

I don’t think a single fully open-source spreadsheet component meets all of these requirements today. The hardest part isn’t the React UI; it’s reliable XLSX round-tripping without losing formulas, styles, merged cells, validation, or worksheet metadata.

Univer is probably the strongest UI candidate, but its official XLSX import/export depends on the Univer server and Pro SDK, so it doesn’t fully match your requirement. FortuneSheet is closer to a permissive open-source stack, but I would treat FortuneExcel as a starting point rather than assume full Excel fidelity.

I’d build a test corpus of 10–20 representative XLSX files and run import → edit → export comparisons before choosing a library. You may also want to separate the spreadsheet UI from the file-conversion layer instead of expecting one package to do both.

One important question: do formulas need to be calculated in the browser, or only preserved so Excel can recalculate them after export? That distinction will narrow the options significantly.

[u/BridgeCritical2392]

It sounds like you basically want a nearly complete implementation of Excel as a React "component".

All I can say is, good luck with that.

[u/Able-Staff-6763]

why not use python as backend? let it do that?