For everyone who builds, checks or signs off on Excel

Take the
guesswork out of Excel.
Trust your models again.

PerfectXL finds the errors in your spreadsheets, shows how a model really works and tracks every change between versions, with the Excel you already use. So you can review faster, hand over safely and decide with confidence.

  • Works with your existing Excel
  • Runs offline on your machine
  • Built with TU Delft

Trusted by audit, finance and risk teams at

PennyMac logo
AZL logo
Coreva Scientific logo
BDO logo
Deloitte logo
Grant Thornton logo
ROBECO logo

Why it matters

Your decisions run on Excel. So do the errors.

Budgets, valuations, provisions and pricing are still built in spreadsheets, and checked by hand. One wrong reference rarely announces itself. It shows up later, in a board decision, an audit finding or a headline.

Up to 94%

of business spreadsheets contained errors in the most thorough field audits

€40M

budget gap for the City of Utrecht after one missed inflation correction in Excel

$92M

lost by Norway’s sovereign wealth fund due to an error in Excel

Products & services

Software for your models, experts for everything else

  • Most complete

PerfectXL Suite

Detect mistakes, understand models and compare versions. Use the tools as offline, stand-alone software, or straight from Excel with the PerfectXL Add-in.

Risk Finder

Audit spreadsheets, detect mistakes, identify risks

Explore

Lists and visualizations for complex models

Compare

Version management, down to formulas and VBA

Highlighter

Temporary colours for data and formula consistency

Try 30 days free

PerfectXL Formula Inspector

Break complex formulas into colour-coded parts and build new ones in smarter ways, step by step.

Service

Excel training

Building good models is a craft. Our training programme helps your team become really good modellers.

Service

Tailor-made Excel projects

No time to build it, or stuck on a model? Our team builds, improves or validates Excel models for you.

Built for your role

Whatever your part in the model, PerfectXL has your back

Every spreadsheet passes through several hands. Each one needs something different.

Model builders

Build and change without breaking things

Catch broken formula ranges and error-prone functions while you work, and see what every change affects.

Model reviewers

Review someone else’s work in minutes

Start every review with a full risk scan and a map of the model, then spend your time where the risks are.

Decision-makers

Sign off on numbers you can stand behind

Get a clear quality report on the models behind a decision, without having to read the formulas yourself.

Advisers

Give clients evidence, not opinions

Test client models against formal guidelines such as FAST and ICAEW, and deliver audit reports they understand.

Client cases

What changes when teams stop checking by hand

It’s without a doubt Top 5 in the world in terms of mitigating human errors, visualizing changes and analyzing potential risk factors.

Pascal Schoneberg

M1KLLC

Insurance

Fewer errors in complex models, faster onboarding
Insurance company VGZ →

Accountancy

Five-minute scans before every review
International accounting firm →

Energy

Missing subsidiary caught before sign-off
Global energy company →

Advisory

No more confidential data hidden in client files
Big Four consultancy →

  • Who is PerfectXL?

Built on research,
not guesswork

PerfectXL is an Amsterdam team with 12 years of spreadsheet risk research behind it. Every check rests on 39 principles for sound Excel models, developed together with TU Delft.

In 2026, Excel professionals at the Global Excel Summit in London voted the PerfectXL Add-in Best Excel Add-in.

Your data stays with you

Offline, stand-alone analysis on your own machine

ISO/IEC 27001 certified

Independently audited information security

Developed with

  • TU Delft
  • Microsoft
  • Erasmus University
  • Microsoft MVPs
  • Software Improvement Group
  • SourceLab

Ready to stop losing sleep
over spreadsheet errors?

One hidden mistake shouldn’t cost your company millions, or cost you your reputation. Get in touch with our experts to see how PerfectXL can safeguard your most critical models, cut your review time in half, and give you total peace of mind.

Let’s make your spreadsheets bulletproof.

  • Run it on your own file, not a canned dataset
  • Nothing leaves your environment
  • 14 days, all capabilities, no card

Start your free trial