Excelerator is a one-person operation. I am the developer, the tutor, the writer, and the designer. There is no team hiding behind a “we”. Just me, a standing desk, and an unreasonable passion for spreadsheets.
I spent 8 years in corporate finance before I decided that teaching Excel was more valuable than using it to make decks nobody reads. So I quit, built this platform from scratch, and started running boutique bootcamps.
Marek Wiśniewski
Founder · Developer · Tutor
One person, many roles
I wrote every line of this platform — Next.js front-end, data layer, content pipeline, the lot. No co-founder, no agency.
I design and deliver every course, workshop, and bootcamp. The syllabus lives in my head and has been stress-tested with 400+ students.
I write all the function docs, articles, and templates. If a sentence is vague, I rewrite it. No ghostwriters, no AI paste-jobs.
YouTube, newsletter, social — all me. I edit my own videos, design my own thumbnails, and answer every reply personally.
Roadmap, UX decisions, pricing, partnerships. Every call about what gets built — and in what order — goes through one person.
Teaching is the core, not a marketing channel. Everything else on this platform exists to deepen the learning, not replace it.
How we got here
First spreadsheet obsession
Built a 3-statement financial model for a university project. Got a C+ on the paper and an A+ on the model. Knew which one mattered.
Started teaching
Began running lunchtime Excel sessions at my first finance job. 6 colleagues turned into 40. HR asked me to make it official.
Went fully online
Published my first YouTube tutorial during lockdown. 200 views. Then 2,000. Then the channel crossed 50k subscribers without a single paid ad.
First live cohort
Ran a 5-day intensive workshop in Warsaw with 14 students. Sold out in 72 hours from a single newsletter post. Knew this format had legs.
Built Excelerator
Quit the corporate gig. Spent 8 months coding, writing, and recording. Excelerator launched quietly — 300 signups in the first week from word-of-mouth alone.
How I work
Anyone can make a list of 200 functions. I'd rather teach 20 so well that you never forget them.
Every tutorial, template, and article ships only when it earns its place. There's no quota to hit, no algorithm to feed.
Excelerator will never be a content farm. I'm one person with a finite number of hours — so I spend them carefully.
I only teach things I've used professionally or seen students struggle with in actual jobs.
Let’s talk
I read every email myself. Whether you’re curious about the bootcamp, want to collaborate, or just want to say that INDEX/MATCH changed your life — my inbox is open.