Notpron
The riddle that calls itself the hardest on the internet, played by editing URLs and reading page source.
Opens in a new tab. We do not control this site and it may have changed since we catalogued it.
How to get the most from it
Notpron sits in Mysteries & Riddles under Learn, filed as rabbit hole.
- Open it when the evening is free. It has no natural stopping point.
- Use a laptop or desktop computer — we file it as desktop only.
- Turn the sound up or put headphones on — it needs audio.
- No account needed — you can start without signing up.
- Go in expecting something brainy, nostalgic and unsettling.
About this category: Logic mysteries, cipher tools, unsolved cases and ARG-shaped sites that never quite explain themselves. Deduction as entertainment.
Good for
- A long evening with nothing planned
- Giving your brain a workout
- A trip back to the older internet
- A little creeping unease
- Trying it with zero commitment
Notpron: quick answers
Is Notpron free?
Yes. Notpron is free to use and needs no account.
Do I need an account to use Notpron?
No. You can use Notpron without signing up for anything.
Does Notpron work on a phone?
Not well. We file Notpron as desktop only, so open it on a laptop or desktop computer.
Is Notpron safe for work?
Yes, we file it as safe for work. It does need sound, so bring headphones.
How long does Notpron take?
We file it as "Rabbit hole": Clear your evening. We warned you.
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