Excel AI & VBA Studio

Work with Excel workbooks, VBA projects, and bounded AI context directly in Visual Studio Code.

Excel AI & VBA Studio is a preview VS Code extension for inspecting supported spreadsheet formats, editing safe workbook content, and working with Excel objects, VBA modules, classes, and UserForms without leaving VS Code.

Important

The workbook grid and VBA Studio are integrated into VS Code. Microsoft Excel does not open merely because a workbook is viewed or exported. The explicit Open in Excel and Open native VBE commands launch or reactivate Excel only when requested.

Current capabilities

Format	Workbook grid	VBA workspace	Bounded AI context
.xlsx	Read and edit	Working project without embedded macros	Yes
.csv, .tsv	Read and edit	Not applicable	Yes
.xlsm	Targeted cell and formatting editing	Yes, when Excel policy allows it	Yes
.xls	Protected read-only view	Yes, when Excel policy allows it	Yes
.xlsb	No integrated grid	Yes, when Excel policy allows it	Yes

• Workbook grid in a VS Code editor tab.
• Theme colors, conditional formatting, comments, and worksheet protection preserved in .xlsx workbooks.
• Integrated A4 print preview, conditional indicators, and structured-formula results.
• Excel & VBA Project explorer with Microsoft Excel Objects, UserForms, Modules, Class Modules, and References.
• VBA properties pane synchronized with the selected component.
• Integrated VBA Studio with project explorer, properties, code, procedures, and supported component creation.
• Light, dark, and high-contrast themes synchronized with the active VS Code theme.
• .bas, .cls, and .frm editing in VS Code, including an interactive, non-executing preview for exported UserForms.
• VBA workspace root and generated .github/copilot-instructions.md so GitHub Copilot can index exported sources.
• Automatic transactional reinjection when supported .bas, .cls, or existing .frm code is saved.
• Standard-module and class creation from VBA Studio or GitHub Copilot.
• Targeted .xlsm value, formula, cell-style, explicit row/column dimension, and supported conditional-formatting editing through an isolated Excel working copy, with conflict detection, persistent backup, and atomic replacement.
• Real Excel tables are preserved as ListObject instances. Multiple disjoint tables may use the same columns, with independent names, filters, stripes, and built-in styles. Existing totals rows are inventoried and preserved, but native creation, totals transitions, and resizing a table that already has totals are refused because Excel would move cells and rewrite formula references.
• The Insert ribbon includes a native chart designer for the complete published XlChartType catalog, editable series, source ranges, axes, titles, legends, labels, colours, markers, and layout.
• Automated creation is offline by default: xlSuggestedChart is inventory-only and xlRegionMap is disabled because Excel may send geographic data to Bing Maps; existing map charts are preserved.
• Classic OOXML charts are reloaded into the designer; modern chartEx objects are detected and preserved natively, with an explicit non-editable count when their richer OOXML cannot be mapped safely.
• Explicit handoff to the real workbook in Microsoft Excel or its native VBE.
• Bounded local Markdown and JSON exports for values, formulas, formats, tables, charts, names, links, validations, comments, connections, and permitted VBA metadata.
• Referencable AI tools #excelVbaWorkbook, #excelVbaWriteModule, #excelVbaDesignWorkbook, and #excelWorkbookDesign, invoked only on request.
• First-time .bas or .cls write-back for an .xlsx creates a new sibling .xlsm, preserves the original byte-for-byte, and returns the exact target path for subsequent writes.
• #excelVbaDesignWorkbook creates complete UserForms with real designer/.frx streams, adds supported visual controls, and creates worksheet Form Control buttons assigned to macros in an existing .xlsm.
• The VBA Controls view inventories worksheet Form Control buttons and ActiveX controls, resolves their public macro targets, and displays a static button-to-macro-to-UserForm flow without running VBA.
• Existing Form Control buttons can be reassigned, and supported worksheet ActiveX buttons can be created or bound to verified macros through the transactional VBA Designer.
• VBA Studio includes a visual UserForm canvas backed by the real COM designer inventory. Standard controls can be added, moved, resized, inspected, and connected to complete VBA event procedures.
• GitHub Copilot can use updateUserFormControl and setUserFormEventHandler through #excelVbaDesignWorkbook, including parameterized events such as KeyDown, BeforeUpdate, and QueryClose.
• GitHub Copilot can create, update, and delete native tables and charts through #excelWorkbookDesign in .xlsx and .xlsm workbooks, with the same transactional safeguards as the integrated editor.
• Open VBA Studio in VS Code creates an isolated, validated VBA workspace in a separate VS Code window and opens the integrated studio there.
• A read-only Enterprise Security Center classifies the selected workbook as restricted, managed, standard, or unknown and explains file, macro/VBA, ActiveX, Protected View, Trusted Location, signature, EFS/OOXML package encryption, Microsoft 365 Cloud Policy, Windows policy, Intune/MDM, and local Microsoft Purview signals.
• No extension telemetry and no API key management by the extension.

Install from a VSIX

Download excel-ai-vba-studio-win32-x64-<version>.vsix, then run:

code --install-extension .\excel-ai-vba-studio-win32-x64-<version>.vsix

You can also use Extensions > ... > Install from VSIX in VS Code.

Build from source

Requirements: Node.js 22, npm, Git, and Visual Studio Code 1.95 or newer.

git clone https://github.com/StephaneSGL/excel-ai-vba-studio.git
Set-Location excel-ai-vba-studio
npm ci
npm run validate
npm run package

The Visual Studio Marketplace release is not available yet. This public repository is currently the official source for the preview.

Quick start

1. Open a supported workbook in VS Code.
2. Use the integrated grid or the Excel & VBA explorer.
3. Open the Enterprise Security Center before using an unfamiliar or organization-managed workbook.
4. Export local context only when you need to inspect it.
5. Reference #excelVbaWorkbook explicitly from a compatible VS Code AI chat.
6. Use Open VBA Studio in VS Code to open a separate Developer window containing the project, controls graph, and real exported sources.
7. Edit and save a supported .bas, .cls, or existing .frm file. For .xlsx, the first .bas/.cls write creates a sibling .xlsm; continue on the returned target. Existing macro-enabled workbooks use validated transactional replacement.
8. Reference #excelVbaDesignWorkbook to create a UserForm, add or reposition supported controls, assign complete control/UserForm event procedures, create or reassign a worksheet Form Control button, or create/bind a permitted worksheet ActiveX control in an existing .xlsm.
9. Use the Insert ribbon or reference #excelWorkbookDesign to create and edit native tables and charts. See the complete choices and limits.

What changes inside XLSX and XLSM

• The first standard module or class applied to an .xlsx is inserted through a controlled hidden Excel instance into a new sibling .xlsm. The .xlsx source is never rewritten.
• A standard module or class created in VBA Studio can be inserted into the .xlsm VBA project.
• Existing UserForm code can be updated. Its designer and .frx resources remain unchanged and are verified before write-back.
• The separate VBA Designer tool can create a complete UserForm with real designer/.frx streams, add or reposition supported controls, assign bounded event procedures, create or reassign a worksheet Form Control button, and create/bind permitted worksheet ActiveX controls.
• Supported standard controls are Label, TextBox, CommandButton, ComboBox, ListBox, CheckBox, OptionButton, ToggleButton, Frame, Image, SpinButton, and ScrollBar.
• UserForm controls can be added, moved, resized, and connected to VBA events on the visual VS Code canvas. Button flows remain a static simulation; Open in Excel provides the real clickable controls and macro events.
• Existing UserForms, controls, buttons, ActiveX data, VBA, and opaque OOXML parts are preserved during targeted cell edits.
• Native table/chart transactions accept .xlsx and .xlsm, create a persistent recovery copy, and verify the requested objects after reopening the working copy in Excel. Workbook opening itself remains package-only and does not start Excel.
• Open in Excel opens the real workbook. Open native VBE opens Excel and its separate VBA editor. Open VBA Studio in VS Code opens a separate VS Code Developer window.

Main commands

Command ID	Purpose
excelAiVbaStudio.openExcel	Launches or reactivates the real workbook only on request.
excelAiVbaStudio.openVbe	Opens the workbook in Excel, then displays the native VBE.
excelAiVbaStudio.openSecurityCenter	Inspects local file and Office security signals without opening Excel or changing policy.
excelAiVbaStudio.openVbaDeveloper	Opens a separate validated VS Code Developer window with the VBA interface and exported sources.
excelAiVbaStudio.exportWorkbook	Creates local Markdown and JSON exports.
excelAiVbaStudio.copyWorkbookContext	Exports and copies bounded workbook context.
excelAiVbaStudio.openVbaExplorer	Opens .bas, .cls, and .frm files and exposes them to Copilot.
excelAiVbaStudio.askCopilotAboutWorkbook	Prepares Copilot Chat with #excelVbaWorkbook and the active workbook.
excelAiVbaStudio.cleanExports	Removes exports managed by the extension.

Shortcut:

• Ctrl+Alt+F11: open VBA Studio in VS Code.

Settings

Setting	Default	Purpose
excelAiVbaStudio.maxRows	200	Maximum exported rows per worksheet.
excelAiVbaStudio.maxColumns	50	Maximum exported columns per worksheet.
excelAiVbaStudio.includeVba	false	Includes VBA only when Excel explicitly permits programmatic access.
excelAiVbaStudio.allowedCustomActiveXProgIds	[]	Exact allowlist for third-party ActiveX ProgIDs; built-in MSForms controls do not need an entry.

Architecture

flowchart LR
  File["Local workbook"] --> Grid["Integrated VS Code grid"]
  File --> Host["Extension host"]
  Explorer["Excel & VBA explorer"] --> Host
  ReadTool["#excelVbaWorkbook"] --> Host
  WriteTool["#excelVbaWriteModule"] --> Host
  DesignTool["#excelVbaDesignWorkbook"] --> Host
  ObjectTool["#excelWorkbookDesign"] --> Host
  Host --> Bridge["Hardened PowerShell bridge"]
  Bridge --> Excel["Controlled Excel COM instance"]
  Excel --> Export["VBA project and bounded local context"]
  Export --> Workspace["VBA workspace root"]
  Workspace --> Explorer
  Workspace --> ReadTool
  Workspace --> WriteTool
  Workspace --> Studio["Separate VS Code Developer window"]
  Export --> Graph["Static button → macro → UserForm graph"]
  Graph --> Studio
  WriteTool --> Route{"Workbook format"}
  Route -->|"XLSX first write"| Bootstrap["Controlled XLSM bootstrap"]
  Bootstrap --> Excel
  Bootstrap --> NewFile["New sibling XLSM"]
  Route -->|"XLSM or XLAM"| Writer["Transactional VBA writer"]
  Writer --> File
  DesignTool --> Designer["Transactional VBA Designer"]
  Designer --> File
  ObjectTool --> ObjectDesigner["Transactional ListObject / ChartObject engine"]
  ObjectDesigner --> File
  Host --> Launcher["Explicit native handoff"]
  Launcher --> ExcelUi["Microsoft Excel or native VBE"]
  ReadTool -. "explicit sharing" .-> AI["AI provider selected in VS Code"]

Loading

The published bundle starts from src/extension.ts and registers only the intended Excel, VBA, and AI surfaces. The repository retains historical upstream sources that are not included in the targeted VSIX.

Excel, VBA, and AI security

• Workbook export uses a dedicated Excel instance and fails closed if macro execution cannot be disabled.
• The Enterprise Security Center is opt-in and read-only. It inspects the selected file, its Mark of the Web, bounded Office 16 policy/preference registry locations, Cloud Policy presence, declared Trusted Locations, Office architecture, fixed Intune/MDM and Group Policy signals, and the enterprise rule that allows or refuses user-defined Trusted Locations, without starting Excel.
• Detected values are separated by technical source: Microsoft 365 Cloud Policy, Windows policy registry for the computer or user, or local preference. The effective table applies Cloud Policy > Windows policy > local preference, shows shadowed evidence, and marks effective managed decisions as locked. A Windows policy key alone cannot prove whether GPO, Intune/MDM, Configuration Manager, or a script delivered it.
• The Center can refresh or copy its local report, open the extension settings, and expose contextual links to Microsoft 365 Apps, Intune, Purview, or GPO diagnostics for an already authorized administrator. It deliberately does not open the inspected workbook; Excel must be started separately before consulting Developer > Macro Security. Opening a portal grants no role. The extension never changes Group Policy, Intune, Cloud Policy, Purview, Trust Center, AccessVBOM, ActiveX, Trusted Locations, Mark of the Web, or the registry.
• Modern OPC LabelInfo.xml and correctly related historical custom properties are parsed structurally. Any stored technical name, tenant ID, method, date, and content-marking bits are shown as unauthenticated local declarations; they do not establish the current display name, confidentiality rank, tenant authenticity, or encryption state.
• unknown means that the final Excel decision cannot be proven from local static evidence. Cloud assignment, certificate trust, antivirus decisions, and policy conflicts can still require confirmation by an administrator or by Excel itself.
• Events, link updates, alerts, and automatic calculation are disabled during controlled analysis.
• The extension never changes Excel's Trust access to the VBA project object model setting or the Windows registry.
• First-time .xlsx VBA bootstrap requires that the user has already enabled Excel's VBA project object-model access. It uses a hidden, owned Excel process with macros disabled, creates only the exact sibling .xlsm, verifies vbaProject.bin, and leaves the source hash unchanged.
• Any path containing the exact .excel-ai-vba-backups component is refused as a write target because it is reserved for recovery copies.
• .xls is never rewritten by the integrated grid.
• Supported .xlsm cell edits are sent to a dedicated Excel instance operating on a working copy, never directly on the original file.
• Before committing an .xlsm edit, the engine checks source hashes, the OOXML package, vbaProject.bin, UserForms, controls, ActiveX data, and opaque resources; it keeps the displaced original in .excel-ai-vba-backups.
• A row or column resize that would move a protected worksheet control or drawing is refused with an explicit message instead of weakening the VML/opaque-part integrity check.
• VBA write-back operates on a copy, validates workbook and source hashes, creates a backup, then replaces the workbook atomically.
• The source-only VBA writer still refuses UserForm designer changes. The separate VBA Designer accepts bounded visual operations only in an existing .xlsm, refuses signed or protected projects, and verifies the resulting designer streams before atomic replacement.
• Worksheet ActiveX creation is denied unless Excel itself permits insertion. Third-party ProgIDs are additionally denied unless the exact value is already present in the user-owned allowlist.
• The direct .xlsm/.xlam source writer does not start Excel. The .xlsx bootstrap and .xlsm Designer use controlled hidden Excel processes with macros disabled; none of these paths runs a macro or changes AccessVBOM.
• Exports remain local, size-bounded, and removable.
• An OOXML package signature makes the workbook read-only in the extension. Detection follows the OPC digital-signature origin/signature relationships and effective Content Types, including arbitrary valid part URIs; malformed, orphaned, external, or otherwise ambiguous signature metadata fails closed. Grid saves, Save As, VBA bootstrap/write-back, UserForms, worksheet buttons, and ActiveX all refuse the mutation rather than invalidate that signature.
• Workbook content is treated as untrusted data, not as instructions for an AI model.
• No workbook is sent to an AI provider automatically.

This is not a network sandbox: Microsoft Excel, Windows, installed add-ins, and security software may have their own network behavior. Read SECURITY.md and PRIVACY.md before using real professional workbooks.

Microsoft references: Cloud Policy for Microsoft 365 Apps, Microsoft Intune, Purview sensitivity labels in Office, Sensitivity Label Information Part, macros from the Internet, Trusted Locations, and Excel macro security.

Preview limitations

• Windows x64 only.
• Microsoft Excel desktop is currently required for COM-based VBA extraction, legacy formats, and targeted .xlsm cell editing.
• Protected, corrupted, or enterprise-restricted workbooks may provide only partial context.
• VBA source access depends on the Excel Trust Center policy already configured by the user.
• Creating the first VBA module in .xlsx also depends on that preconfigured Trust Center policy; the extension never enables it.
• UserForm and button creation requires an existing local .xlsm, Excel desktop, and VBA project-object-model access already enabled by the user. Signed and protected VBA projects are refused.
• The interactive VS Code preview simulates control state only and never runs event procedures; real VBA behavior remains an explicit action inside native Excel.
• Integrated .xlsm editing supports values, formulas, cell styles, explicit row heights and column widths, the five conditional-formatting presets exposed by the ribbon, and native worksheet tables/charts through their dedicated designers. Worksheet structure, implicit dimension resets, merges, unsupported/PivotChart objects, controls, buttons, existing-rule edits, rule reordering, and partial rule deletion are refused.
• The visual UserForm designer supports the standard-control toolbox, positioning, sizing, core properties, and event procedures. Nested-container editing, z-order, font/color styling, images, multi-selection, copy/paste, and native VBE parity remain future work.
• Excel or enterprise policy can block ActiveX insertion even when the extension request is valid. The extension reports that refusal and never weakens Trust Center settings automatically.
• The Security Center does not authenticate to Microsoft 365, resolve current sensitivity-label display names or their tenant-defined rank, validate certificate trust chains, parse encrypted/legacy CFB LabelInfo streams, diagnose every legacy XLS encryption scheme, attribute a Windows policy value to GPO versus Intune, or replace Intune, Group Policy Results, Microsoft 365 Apps admin center, Defender, or Purview auditing.

Version history

Version	Summary
0.6.0	Adds native editable Excel tables and charts, including multiple disjoint same-column tables and the complete published XlChartType catalog. It also adds a read-only Enterprise Security Center with explicit policy provenance and fail-closed workbook capability levels.
0.5.1	Fixes worksheet button verification after Excel normalizes OnAction casing and keeps raw export JSON out of progress notifications.
0.5.0	Adds the visual UserForm canvas, native form/control inventory, control positioning and property updates, plus bounded complex VBA event assignment for Copilot and the visual editor.
0.4.0	Adds the worksheet Controls view, static button-to-macro-to-UserForm graph, Form Control reassignment, permitted ActiveX creation/binding, and a separate VS Code Developer window. It also fixes false .xlsm worksheet-features save refusals caused by grid hydration.
0.3.0	Introduced real UserForm designer/.frx creation, 12 standard controls, worksheet Form Control creation, and broader native formatting edits. These operations are transactional and verified against a live Excel copy.
0.2.1	Added first-write .xlsx to sibling .xlsm conversion for new standard modules and classes. It preserved the source and returned the exact target path for subsequent writes.
0.2.0	Added transactional VBA write-back and targeted native .xlsm cell/style editing. It also completed save, revert, backup, and hot-exit protection for the embedded grid.
0.1.7	Activated advanced ribbon data, formula, formatting, import, chart, and page-layout actions. It removed the remaining visible placeholder actions.
0.1.6	Reduced initial webview JavaScript from about 2 MB to 219 KB through progressive loading. It also removed redundant workbook parsing and traversal.
0.1.5	Synchronized the spreadsheet and VBA Studio with VS Code light, dark, and high-contrast themes. It improved focus, selection, warning, and status styling.
0.1.4	Added the VBE-style integrated editor, real VBA source files, module/class creation, and Copilot workspace indexing. It stabilized the generated VBA directory on Windows.
0.1.3	Added high-fidelity colors, conditional formatting, comments, protection, project exploration, properties, and UserForm preview. It also improved print preview and structured-formula display.
0.1.1	Added the Excel-style ribbon and its core editing/navigation commands. It established public documentation, licensing, notices, and contribution rules.
0.1.0	Established the Windows x64 Excel/CSV editor, native Excel/VBE handoff, bounded workbook export, VBA explorer, and AI read tool. It removed unrelated viewers, telemetry, and sponsor integrations from the packaged extension.

Roadmap

• Improve grid fidelity and accessibility.
• Expand the visual UserForm designer with nested containers, z-order, styling, multi-selection, and copy/paste.
• Expand the integrated Formula, Data, and Developer surfaces.
• Add synthetic workbooks and regression coverage for unsupported macro and formatting cases.
• Complete English and French localization.
• Prepare Marketplace updates after publisher configuration.

The roadmap states direction, not a release date or feature promise.

Development and contribution

npm ci
npm run validate

Test workbooks must be fully synthetic. Never submit company data, credentials, secrets, or proprietary VBA.

• Reproducible bugs: GitHub Issues
• Questions and ideas: GitHub Discussions
• Vulnerabilities: private GitHub reporting
• Contribution rules: CONTRIBUTING.md

License and ownership

This repository is public and source-available, but it is not open source under the Open Source Initiative definition.

Excel AI & VBA Studio-specific contributions distributed from version 0.1.1 use the PolyForm Noncommercial License 1.0.0:

Use	Permission
Personal study, research, experiments, hobbies, and amateur projects without an anticipated commercial application	Permitted
Education, charitable work, public research, public safety or health, environmental protection, and government use covered by PolyForm	Permitted
Modify or redistribute for a permitted noncommercial purpose while preserving required notices	Permitted
Use in business operations, paid client work, resale, monetization, or integration into a commercial product or service	Separate written commercial license required

• Portions originating from Office Viewer by Weijan Chen remain available under their original MIT license.
• Every third-party dependency retains its own license.
• Versions or commits already distributed under MIT retain the rights previously granted; a later license change cannot revoke those earlier rights.

See LICENSING.md for the plain-language summary and complete allocation. Required notices remain in NOTICE.md, LICENSES/OFFICE-VIEWER-MIT.txt, and THIRD_PARTY_NOTICES.md.

Microsoft, Visual Studio, Visual Studio Code, Excel, and VBA are trademarks of their respective owners. This independent project is not published or endorsed by Microsoft.