Migrate VB6 to .NET Blazor

with agentic AI purpose-built for modernization

Our team runs your application through VELO, which automates up to 95% of the conversion into idiomatic C# and Blazor. What you buy is the beta-ready output: a modernized codebase that compiles and runs, at a price fixed before work begins.

Pre-release · Early access

Get early access to VELO Self-Serve

Sign up for the pre-release of our self-service platform, and be first to run your own VB6 assessment and modernization directly, no engagement required.

Get Started
No cost and no commitment. We'll email you when it's your turn.
VB6 to Blazor conversion walkthrough
Your path from VB6 to Blazor
Start here 01 Assessment Know your coverage, timeline, and price Free · 1 day
02 Forward Deployed Engineer An engineer converts one of your real modules 1 week · paid engagement
The VELO engagement 03 Beta-ready output We run your full codebase through VELO. You get a working Blazor app that compiles and runs. Fixed price
04 Production AI Squad takes it to a tested release candidate Fixed price · optional

Steps 1 and 2 scope and prove the work. Step 3 is the VELO engagement itself, and there is nothing for your team to install or operate.

Microsoft Solutions Partner - Digital and App Innovation, Azure

35+ years and 1B+ lines of legacy pattern recognition, proven at enterprise scale on MS Foundry.

THOMSON REUTERS UTAH STATE COURTS EXACT HOLDING

The limitations of VB6 vs. a Modern Web App

Still on VB6

What stays out of reach

×No API surface for AI agents to call
×Business logic locked inside desktop forms
×Data siloed away from analytics and AI services
×Every integration is a custom workaround
×Talent pool shrinking every year
On Blazor & Azure

What opens up

Modern APIs connect every system and workflow
AI agents can orchestrate your business logic
Data reachable by Azure AI and analytics services
Compliance, security, and audit trails built in
Engineers ship in C# and .NET, a stack you can hire for

Only 14% of organizations have reached the highest level of cloud maturity. The gap is becoming a chasm. NTT Data, 2026 ↗

Where you land

The same application, on a stack your team can actually hire for

Every layer of the VB6 stack has a modern equivalent waiting on the other side.

VB6 today
VB6 FormsDesktop only
Class & std modulesUndocumented
DAO / ADOLegacy drivers
ActiveX / COM32-bit bound
MSVBVM60.dllUnsupported
Windows desktopNo cloud path
VELO
Blazor on Azure
Blazor componentsAny browser
C# servicesTyped & testable
Entity FrameworkAzure SQL
.NET librariesFully managed
.NET 10 runtimeSupported
Azure App ServiceCloud-native
What converts

VELO transforms VB6 construct by construct

Select a construct to see the actual transformation.

How it works

How VELO works

Phases 1 and 2 are fully automated. Phase 3 is human-led, when you want it.

VB6 Your codebase
VELO Fully automated · phases 1–2
Phase 01 · Deterministic Analysis Fully automated

Agents inventory the codebase and map it to .NET, before a single line is converted.

Phase 02 · AI-Driven Transformation Fully automated

Agents convert the logic to .NET and Blazor, then validate the result before it ships.

Output · Beta-ready

Compiles and runs. Still needs refinement and testing before it's production ready.

Phase 03 · Human-Led Human-led

Senior engineers close the gaps automation can't: judgment calls and desktop-to-web rework.

Output · Production-ready

AI Squad gets you to a tested, cloud-native release.

ASSESS

Parses your VB6 project into a structured form, then scores every form and data-bound grid to separate UI screens from report candidates — flagging edge cases like vouchers and receipts instead of mis-scoring them.

The 70% wall

Generic AI tools stall exactly where your VB6 logic gets hard.

General-purpose AI tools get roughly two-thirds of the way through a VB6 codebase, then stall. What's left is the hardest part: tangled global state, ActiveX quirks, and undocumented data access.

That remaining gap is where weeks of manual engineering go. VELO's agents are trained on VB6 patterns specifically, which is what closes it.

DIY AI tools (Copilot, Cursor, Claude, Codex)~70%
VELO, purpose-built for VB6up to 95%

The free assessment scopes the remainder precisely before you commit.

Want to run VELO yourself?

Sign up for the pre-release of our self-service platform, and test it on your own VB6 codebase, no engagement required.

Get Started
The comparison

How VELO compares to a manual rewrite or a generic AI tool

Every path answers the same four questions. Only one answers them upfront.

← Swipe to compare →
Manual rewriteGeneric AI toolsVELO
Timeline 12–24 months, rebuilt from scratch Fast start, then stalls indefinitely at the 70% wall Up to 20x faster than a manual rewrite
Cost certainty Overruns of 2–3x are common "Free" tool, but the last 30% bills as engineering time, indefinitely Fixed price, quoted after assessment
Business logic Rebuilt from memory and whatever documentation survived Approximated; breaks on complex, tangled VB6 patterns Extracted and converted systematically, validated against the original
Who's accountable Whoever's still on the team when it ships You, once it stalls VELO, through beta-ready delivery; AI Squad optional to production

Figures reflect VELO enterprise engagements anchored to comparable manual-rewrite scope. See assessment for a quote specific to your codebase.

The path

Priced and proven before you commit to the next step.

Each checkpoint is scoped and priced before the next one begins.

Scope your VB6 codebase before spending a dollar

We run ByteInsight, our automated VB6 codebase scanner, against your codebase to catalog every form, module, and dependency, then walk you through the automation coverage estimate and scope report.

  • Runs in about a day
  • Followed by a walkthrough of results and estimates with the team
  • No cost and no commitment, under NDA
Validate the approach on one real module

A Forward Deployed Engineer works alongside your team to convert one real VB6 module, so you can judge VELO's output against your own code before committing further.

  • A one-week paid POC engagement
  • You review real converted output from your codebase, not a demo
  • Findings feed directly into the fixed-price quote
We run your application through VELO

Our engineers put your full codebase through the agent pipeline. Core architecture is established in C# and Blazor, compiles, and launches your main forms. This is where the bulk of the 95% automated conversion happens.

  • Fixed price, quoted from the assessment
  • You receive full source code, a validation report, and documentation of what remains
  • Output is beta-ready: it compiles and runs
  • Nothing for your team to install, configure, or operate
Close the last mile, without staffing up

Senior engineers take the beta-ready application through testing, stabilization, and integration to a production release candidate.

  • Fixed price, optional add-on
  • Your team can also take the beta-ready codebase and finish it in-house
  • Either path, you own the final code with no vendor lock-in
Security & trust

Your VB6 source code stays yours.

Modernization puts decades of business-critical code in front of an AI system. Here's what happens to it.

Processed in a dedicated Azure environment

VELO runs natively on MS Foundry in a dedicated environment operated by our team. Your code never trains a shared model.

Deterministic mapping

We deterministically assess and map your codebase, so the output ensures the correct business logic.

Backed by two decades with Microsoft

A Microsoft relationship spanning more than 20 years is what VELO's security posture is built on.

Check the work

Don't take our word for it. Read the converted code.

A full reference migration, source available before and after, no form required.

Frequently asked

Questions about VB6 modernization

It depends on the size and complexity of the application. A typical mid-sized VB6 application (100K–500K lines) can reach beta-ready in weeks using VELO's automated conversion. The free assessment gives you a precise timeline before you commit. Larger applications with heavy ActiveX or COM dependencies may take longer, still significantly less time than a manual rewrite.

We're building VELO Self-Serve so you can run your own VB6 assessment and modernization directly — it's currently in pre-release, and you can sign up above for early access. In the meantime, VELO is available today as a managed service: you share your VB6 source under NDA, our engineers run it through the platform, and you receive the modernized codebase along with a validation report at each milestone. Either way, there's no software for your team to install or maintain, and you own the resulting code outright.

Yes. VELO extracts and converts the business logic in your VB6 application, including rules in class modules, standard modules, and event handlers, and validates the result through automated testing against the original application's behavior.

No, it's an automated conversion. VELO analyzes your existing VB6 code and transforms it into the target framework, producing idiomatic C#/Blazor code that preserves your application's behavior and structure.

Blazor on .NET 10 running on Azure is the recommended target for a cloud-native, web-based result. Where your team's skills or infrastructure call for it, C# with WinForms is also available, keeping a familiar desktop experience on the same modern .NET foundation.

Yes. For large VB6 applications, VELO can convert in phases, module by module, so your team can validate each phase before moving to the next.

Your source code is shared with us under NDA and processed within a dedicated Azure environment. It is never used to train shared models and never shared across engagements. We accommodate data residency requirements within Azure's regional infrastructure.

You get the full converted source code, with no ongoing licensing fees and no vendor lock-in. Your team can take it to production, or our AI Squad can finish the last mile, testing, stabilization, and integration, at a fixed price.

The free assessment shows you upfront what percentage of your application VELO can automate, so there are no surprises, and anything outside automated coverage gets scoped clearly as part of the fixed-price quote.

Your VB6 application already works.

Let's make sure it keeps working somewhere better. Sign up for the pre-release of our self-service platform, no cost and no commitment.

Get Started