Open-Source Excel Alternatives (2026, Free)
Identifying Microsoft Excel · Mark source
People look for a Microsoft Excel alternative when they want an OSI-style license, a local .xlsx editor, or a suite they can self-host. This hub lists tools we verified on 2026-10-20. Excel is named only to identify that product class.
- LibreOffice Calc — Spreadsheet module of the MPL-2.0 LibreOffice suite. Latest branch 26.8.1.
- ONLYOFFICE — AGPL-3.0 OOXML office suite (Docs server + desktop editors). Latest GitHub release v10.0.0.
- GridCraft — Pure-Rust clean-room Excel-style spreadsheet in the ArtCraft suite (alpha).
How we pick
- Open-source license files we could open on an official host.
- Spreadsheet editing (not an AI slide generator).
- Documented platforms from the project’s own README or site.
- Honest maturity: GridCraft’s README calls it alpha; we do not claim Excel parity.
Comparison
| Name | License | Price | Platforms | Runs locally | Maturity | Last release |
|---|---|---|---|---|---|---|
| LibreOffice Calc | MPL-2.0 | free | Windows, macOS, Linux | Yes | See page | 26.8.1 |
| ONLYOFFICE | AGPL-3.0 | free | Windows, macOS, Linux, Docker, Web | Yes | See page | v10.0.0 |
| GridCraft | MIT OR Apache-2.0 | free | macOS, Windows, Linux, BSD, Web | Yes | See page | v0.8.0 |
Why these three
The 2026-10-20 check covers LibreOffice Calc, ONLYOFFICE, and GridCraft.
LibreOffice Calc is the spreadsheet in TDF’s suite. Official licenses page: MPL-2.0. Latest branch 26.8.1 (TDF, 8 October 2026). Previous mature branch 26.2.6 until 30 November 2026. GitHub LibreOffice/core mirror: 4,536 stars (read-only; use Gerrit).
ONLYOFFICE is an AGPL-3.0 OOXML suite. DocumentServer 7,032 stars, release v10.0.0 (2026-10-12). DesktopEditors 5,602 stars, v10.0.0 (2026-10-13).
GridCraft is a new GitHub project (created 2026-10-07) with 5,913 stars and 2,742 forks, dual MIT OR Apache-2.0, latest release v0.8.0, labeled alpha. Same ArtCraft family as WordCraft and PhotoCraft.
Sourced snapshot (2026-10-20)
| Field | LibreOffice Calc | ONLYOFFICE | GridCraft |
|---|---|---|---|
| License | MPL-2.0 (official page) | AGPL-3.0 | MIT OR Apache-2.0 |
| Stars (host we opened) | 4,536 (GitHub core mirror) | 7,032 (DocumentServer) | 5,913 |
| Last release in this check | 26.8.1 (2026-10-08) | v10.0.0 | v0.8.0 (2026-10-18) |
| Job | Suite spreadsheet | OOXML collab + desktop | Clean-room XLSX editor |
| Maturity | Long-standing | Long-standing | README: alpha |
| Quality vs Excel | Not independently tested | Not independently tested | Not independently tested |
Who should switch
- Need a production-proven free spreadsheet this week: LibreOffice Calc from libreoffice.org/download.
- Need self-hosted real-time OOXML editing: ONLYOFFICE DocumentServer (Docker/deb/rpm) or Desktop Editors.
- Want a new Rust-native .xlsx app and accept alpha risk: GridCraft v0.8.0.
- Need slides, not sheets: PowerPoint alternatives (DeckCraft, LibreOffice Impress).
- Need a word processor: Microsoft Word alternatives (WordCraft).
Limitations we actually sourced
GridCraft’s own README: alpha; inventory ≠ working implementations; ~50% ready (vendor). LibreOffice 26.8.1 is a bug-fix of 26.8; production users may stay on 26.2 until 30 November 2026 (TDF). ONLYOFFICE’s AGPL-3.0 is a copyleft network license — read the LICENSE if you will offer it as a service. We did not test pivot fidelity, VBA macros, or Power Query.
Setup notes
Calc: installers on libreoffice.org (Windows x86-64 / ARM64, macOS Apple silicon / Intel, Linux rpm/deb). ONLYOFFICE: GitHub v10.0.0 assets (deb/rpm/exe for Docs; AppImage/EXE for Desktop). GridCraft: GitHub v0.8.0 signed desktop/web builds, or cargo run --release -p gridcraft. None of those installers were run on a forkalt machine.
License notes
Summaries, not legal advice. MPL-2.0 (Calc) is file-level copyleft. AGPL-3.0 (ONLYOFFICE) extends copyleft to network use. GridCraft is permissive dual MIT/Apache-2.0; GitHub’s API field still shows Apache-2.0 only.
Related
Listed options
LibreOffice Calc
Spreadsheet module of the MPL-2.0 LibreOffice suite. Latest branch 26.8.1.
ONLYOFFICE
AGPL-3.0 OOXML office suite (Docs server + desktop editors). Latest GitHub release v10.0.0.
GridCraft
Pure-Rust clean-room Excel-style spreadsheet in the ArtCraft suite (alpha).
FAQ
What is the best free Microsoft Excel alternative right now?
Among options we sourced on 2026-10-20, LibreOffice Calc is the long-standing spreadsheet (MPL-2.0, suite 26.8.1). ONLYOFFICE is the AGPL OOXML collab suite (DocumentServer 7,032 stars, v10.0.0). GridCraft is a new pure-Rust XLSX editor (MIT OR Apache-2.0, 5,913 stars, v0.8.0, alpha). “Best” depends on whether you need a mature suite, self-hosted co-editing, or a new Rust codebase. We have no bake-off.
Is GridCraft a drop-in Excel replacement?
No. Its README calls it alpha and estimates about 50% ready for real work. The 513-function figure is a parity inventory, not a count of working implementations.
Can I keep .xlsx files?
GridCraft’s README says XLSX is native. LibreOffice and ONLYOFFICE both document OOXML open/save. We have not independently round-tripped a pivot-and-chart workbook.
What about Google Sheets?
Out of scope. This hub is open-source software you can run locally or self-host.
Sources & verification
- https://github.com/storytold/gridcraft
- https://www.libreoffice.org/about-us/licenses/
- https://github.com/ONLYOFFICE/DocumentServer
- https://commons.wikimedia.org/wiki/File:Microsoft_Office_Excel_(2025%E2%80%93present).svg
- https://commons.wikimedia.org/wiki/File:Excel-application_Wiki_client_(en).png
License notes are not legal advice. Read the original LICENSE. Trademark & disclaimer.