Fun quizzes that cover only what matters.
Built for non-engineers who work with engineers —
and it fits into your spare minutes.
Say goodbye to outdated study methods. Build only the skills the coming era actually demands.
Memorizing syntax and fighting errors
Endless hours of “writing practice”
Dropout rate over80%
"One tiny typo and everything breaks…"
"I lost 3 days just setting up my environment…"
* Dropout rate from general surveys on self-taught programming
Directing AI + reviewing its design
Training your ability to read and choose code
Learning on your phone, in spare minutes
Not writing skills —
Reading skills.
65% of our learners started as beginners or had given up before.
Their quiz accuracy is still93%.
Three essential skills instead of long lectures.
We distilled just what it takes to thrive in the AI era.
01PLAN
The ability to put "what to build" into words — the foundation for giving AI precise instructions.
02REVIEW
The ability to judge AI-written code, spotting bugs and inefficiencies on the spot.
03PROMPT
How to communicate so AI performs at its best. Prompting fundamentals, learned systematically.
PENTA IN NUMBERS
From our user survey72% of learners are non-engineers.
Sales, marketers, students — everyone.
The occupation completing the most lessons per person?Sales / BizDev— business roles are the deepest learners.
63% were beginners or had given up before
Mostly beginners — yet quiz accuracy is93%. The difficulty is tuned so no one quits.
27%learn before bed
tied for #1 study time
27%learn while commuting
tied for #1 study time
23%started via word of mouth
1 in 4 were referred
* Aggregated from in-app surveys (176–177 responses, as of Aug 2026). Lessons completed per occupation is the average from learning logs (as of Sep 2026).
16+ courses, 3,050+ questionsEach course takes just a few hours to reach explain-it-to-others level.
Take them in any order. Not sure? Start with the beginner courses that 76% choose first.
Tap any card for a peek inside.
Beginner#1 first courseGraduate from "it just kind of works." From packets to IP addresses, grasp how the internet actually moves data — as one connected story.
BeginnerAn IT primer that starts from the phone you use every day — until APIs, servers, and the cloud all turn into words you understand.
BeginnerUnderstand every AI behavior through one core idea: "AI is just predicting the next word."
IntermediateAuthentication vs. authorization, password storage, MFA, SSO, and OAuth. What really happens behind identity checks and key exchanges.
IntermediateWhy have defenders been losing for 20 years? Learn realistic defense from the asymmetric structure of attack and defense.
BeginnerThe "request counter" that connects services to each other. From requests and responses all the way to webhooks and AI integrations.
IntermediateTalk about "hard to use" with science instead of gut feeling. From cognitive load to dark patterns.
BeginnerWorking software and conversations over perfect plans. Grasp the essence of Scrum, sprints, and the definition of done.
IntermediateStore data in order, retrieve it in an instant. From how tables work to the basics of SQL.
AdvancedThe inside story of testing and quality. A QA primer that lets you discuss test coverage with engineers.
BeginnerWhat happens behind every cashless payment. Follow the money from authorization to settlement and chargebacks.
BeginnerThe moment you tap one like, multiple systems spring into action behind the scenes. Trace the whole journey until an app reaches the store.
BeginnerIt's not "up in the sky" — it's computers you rent as needed. Learn to discuss "how much to hand over" as an equal.
BeginnerA cheap CPI doesn't mean success. Learn to read ad and app metrics — and decide the next move from the numbers.
IntermediateDecode what "raised $500K at a $5M valuation" really means — from equity math to what VCs are after.
BeginnerStaffing, contract development, system integrators, SaaS — 'IT companies' sell and earn in totally different ways. See through the work from the business model.
New courses on the way
Check the app to see which
big question comes next.
* First-course share and the #1 badge are from the in-app survey "the course you chose first" (as of Sep 2026)
Try the quizPulled straight from the 3,050+ questions
in the app. Tap to check your answer.
* Real questions and explanations from the app, translated from Japanese (only lesson-context references adjusted)
Pick a course, learn through dialogue, lock it in with quizzes.
It feels like a game, so you never get bored.
Just choose a topic you're curious about from 16+ courses. The roadmap keeps you on track.
Chat-style lessons with Penta. Just the key points, explained gently.
True/false, multiple choice, matching. Varied quizzes make it stick.
Built to keep you goingLearning only works if you keep at it. Streaks, friends, and rankings nudge you toward just one more question.
Your consecutive learning days are tracked, so daily progress becomes visible — and fun. The current record is a 35-day streak.
You can see how your friends are doing, so you keep each other motivated.
Your effort shows up in the rankings. Friendly, game-like competition keeps motivation high.
BEFOREAFTER
Pick up the skills of the AI era, and both your work and your life change in a big way.
A task that took 30 minutes every day, done in 5 minutes with a tool you built yourself. It changes how you spend your time.
30 min of manual work dailyJust 5 minutes
You can express what you want in technical terms, so rework plummets and projects move smoothly.
Endless reworkUnderstood the first time
Be known as the person who gets tech — your standing rises and you become the link between departments.
Talking past each otherThe go-to person
What learners sayActual reactions from learners, via X and user interviews. Posts appear in their original Japanese.
I open the app without meaning to study. It feels closer to checking social media.
"What courses is everyone taking?" "Anything new in the feed?" — I just end up opening it.
The bar is suddenly high once you're in the field, so having Penta could really help.
It'd be fun if the Penta I picked could talk and teach me out loud.
* Embedded public posts from X, plus summarized user-interview quotes translated from Japanese. Individual impressions.
Clear up every last doubt before you start.
That's exactly who this app is for. Every technical term is untangled one step at a time with analogies and quizzes. Stack up enough small wins, and before you know it you can follow conversations with engineers.
There's no required quota. One lesson during your commute or lunch break is enough. Short daily sessions beat long occasional ones — consistency is the real shortcut.
No. It's built for non-engineers — marketers, project managers, designers, and other business professionals. The focus isn't on writing code, but on talking with engineers at eye level.
Yes, the app supports both iOS and Android. You can start today from the App Store or Google Play.
The download is free. Give it a try, no strings attached.
A slightly scatterbrained, thoroughly logical mentor from Antarctica.
Every lesson unfolds as a conversation with Penta.
Hey hey, I'm Penta.
Nearly froze from staring at ice too long, got ignored for 30 minutes after confessing to a cat — and still counts both as 'new discoveries.'
Servers are waiters, databases are refrigerators. Explains systems through restaurants and houses — never hides behind jargon.
Counts the scales on mail-order fish (passed out at 3,000) and lines up carved ice pellets by size, for fun.
The room is a mess and whole days vanish looking for things. Once found a two-year-old saury in the back of the fridge.
Between lessons, expect Antarctic-grade tangents and little jokes.
Just 3 minutes of quizzes a day.
16+ courses and 3,050+ questions to stack up your IT understanding.
Somewhere, every day, someone is learning with Penta.
私も利用させていただいていますが、わかりやすくて、すごく良いアプリです！✨ユーザーさんどんどん増えていきそうです！
AI時代にぴったりですね。 単語知らないとAIの指示効率下がるのは常々感じています
最近凄い勢いでコース完了させてる #Penta
APIコースも卒業した API少しは詳しくなったかも🐯 #Penta
