Protect Your Excel VBA Code from Reverse Engineering

Compile Excel macros into native DLLs — your financial models, add-ins, and custom functions stay hidden inside compiled bytecode.

Why VBA Password Protection Fails for Excel

If you distribute Excel workbooks or add-ins with VBA macros, your code is at risk. The built-in VBA project password can be removed in seconds using freely available tools. Once bypassed, anyone can read, copy, or modify your macros — including financial models, pricing algorithms, and proprietary calculation logic.

Third-party "obfuscators" only rename variables and add junk code. The logic remains in plain VBA, fully readable in the Visual Basic Editor. For commercial Excel add-ins and workbooks, this offers no real protection.

The Solution: Compile Excel VBA to Native DLLs

VBA Padlock takes a fundamentally different approach. Instead of hiding VBA source code behind a breakable password, it compiles your macros into native 32-bit and 64-bit DLLs. The original VBA code is transformed into bytecode that cannot be decompiled back to the source.

Your Excel workbook (.xlsm) or add-in (.xlam) contains only a thin VBA Bridge module — a few lines of code that load the DLL and route function calls. All your intellectual property lives inside the compiled DLL, completely invisible to anyone opening the VBA Editor.

Write

Write your Excel VBA macros in VBA Padlock Studio with syntax highlighting and autocomplete.

Compile

Click Publish to compile into signed 32-bit and 64-bit DLLs. A VBA Bridge is generated automatically.

Distribute

Ship your .xlsm or .xlam with the bin/ folder. Users run macros normally — the DLL handles everything.

See It in Action

Left: your protected code compiled into the DLL. Right: the thin VBA caller in your Excel workbook.

Protected Code (VBA Padlock)

Function CalculateDiscount(Price, DiscountRate)
    If DiscountRate < 0 Or DiscountRate > 1 Then
        CalculateDiscount = Price
    Else
        CalculateDiscount = Price * (1 - DiscountRate)
    End If
End Function

Sub WriteToCell(CellAddress, Value)
    Application.ActiveSheet _
        .Range(CellAddress).Value = Value
End Sub

Caller Code (Excel VBA Editor)

Sub Demo_CalculateDiscount()
    Dim Price As Double
    Dim Rate As Double
    Dim FinalPrice As Variant

    Price = 100: Rate = 0.15

    FinalPrice = VBAPL_Execute( _
        "CalculateDiscount", Price, Rate)

    MsgBox "Final: $" & _
        Format(FinalPrice, "0.00")
End Sub

Excel VBA Protection in Action

Real workbook and add-in scenarios protected with VBA Padlock.

VBA Padlock code editor showing Excel VBA code to compile — Excel VBA source code in VBA Padlock before compilation.

Excel worksheet using a protected custom VBA function — Protected Excel custom function running in a workbook.

Excel VBA editor wrapper calling VBAPL_Execute for a custom function — Thin VBA wrapper that calls compiled Excel logic.

What You Can Protect in Excel

VBA Padlock supports all Excel VBA scenarios — from simple workbook macros to commercial .xlam add-ins and custom worksheet functions.

Workbook & Add-in Protection

Compile .xlsm workbooks and .xlam add-ins into secure DLLs. Distribute commercial Excel tools without exposing a single line of source code.

Financial Models

Protect proprietary calculation logic, pricing algorithms, and risk models from prying eyes.

Custom Worksheet Functions

Ship proprietary UDFs without exposing the formulas or algorithms behind them. Users see the result, not the logic.

Data Automation & ETL

Secure ETL pipelines, data transformation routines, and reporting macros that process sensitive information.

Excel Add-in Distribution

Distribute commercial .xlam add-ins with full source code protection and integrated license key activation.

Licensing & Activation

Add hardware-locked license keys, trial periods, and online activation to any Excel VBA project — built into the DLL.

Need a step-by-step walkthrough?

Read the dedicated Excel tutorial

Follow the full process to protect an Excel workbook or add-in with VBA Padlock.

Frequently Asked Questions

Can VBA Padlock compile Excel add-ins (.xlam)?

Yes. VBA Padlock compiles VBA code from .xlsm workbooks and .xlam add-ins into 32-bit and 64-bit DLLs. Your protected add-in works exactly the same way — users load it in Excel and all your macros run from the compiled DLL behind the scenes.

Does my compiled code still have access to the Excel object model?

Absolutely. Your compiled VBA code retains full access to the Excel COM object model — Workbooks, Worksheets, Ranges, Charts, PivotTables, and all other objects. There is no sandbox or limitation.

Can I ship custom worksheet functions (UDFs) from a compiled DLL?

Yes. You write your UDF logic in VBA Padlock, compile it, and call it from a thin VBA wrapper function in your workbook. The wrapper calls VBAPL_Execute and returns the result to the cell. The actual calculation logic stays hidden inside the DLL.

Will end users need to install anything besides Microsoft Excel?

No. End users only need Microsoft Excel (2016 or later, 32-bit or 64-bit). You distribute your .xlsm or .xlam file alongside a bin/ folder containing the compiled DLLs. No runtime, no framework, no admin rights required.

Can I add license key activation to my Excel VBA project?

Yes. VBA Padlock includes a complete licensing system with hardware-locked activation keys, trial periods, online activation, and deactivation. All licensing dialogs and logic are built into the compiled DLL — no extra code needed in your Excel file.