1B people use ChatGPT.
You need an unfair advantage.

Mnemosphere's workflow tools allow for multi-model cross-checking, self-critique, and parallel synthesis until the answer is leagues ahead. The result: you win arguments, get hired, close deals, and produce work the other billion never will.

Get started See features

Plans start from $25/mo

Prompt›Write a short story about a lighthouse keeper who finds a letter in a bottle.

GPT-5.4

The lighthouse had taught Jonah precision but not possibility. Every dusk he lit the wick, checked the prism, and logged the weather in the same careful hand.

Then one pale morning a green bottle clinked against the rocks below the tower. Inside was a letter, folded three times, sealed with wax the color of bruised plums.

He read it once for the words, once for the tremor in them, and once for the line he could not set down:

That evening, with the storm lamp buzzing at his shoulder, he wrote back. By dawn, the light he had kept for passing ships had turned inward and mapped a path out for himself.

Claude 4.7 Opus

Salt had erased the signature, but not the courage stitched into every sentence. The writer never begged for rescue; they only asked to be witnessed.

Jonah carried the page up to the lantern room and read it while the beam wheeled over black water, each pass making the tower feel less like a post and more like a threshold.

On the fourth reading he understood the letter wasn't a relic. It was an invitation.

He kept one sentence in his pocket until the lighthouse stopped feeling like duty and started feeling like a gate.

Gemini 3.1 Pro

He mapped every clue with methodical certainty: ink composition, tide direction, cork age, and the probable launch point somewhere east of the shoals.

The data concluded the sender was long gone. The ache in the handwriting suggested otherwise.

So Jonah closed the ledger, warmed his hands over the stove, and did the single thing no model endorsed: he answered the letter and cast it back into the tide.

Award-Winning Story.

Cherry pick the best lines from each model.
Build the ultimate answer.

1Explain quantum computing to a 5-year-old

2Explain quantum computing to a high-schooler

3Explain quantum computing to a CS undergrad

4Explain quantum computing to a physics PhD

5Explain quantum computing to a VC investor

🧸 5-year-old

🎒 High-schooler

💻 CS undergrad

🔬 Physics PhD

💰 VC investor

Parallel Prompts

Fire multiple prompts at once

Explore multiple directions instantly.
Spot subtle nuances and perfect your ideas.
Compress hours of research into seconds.

Superpowers ChatGPT users can never have.

1-click Critique

Critique the AI. Generate masterpiece answers nobody else is getting.

Summarize how the EU AI Act affects most commercial AI deployments.

GPT-5.5

The EU AI Act introduces a risk-tiered framework classifying systems by their potential for harm.

Most commercial deployments will fall under “limited risk,” requiring only transparency obligations.

Compliance costs should remain manageable for most companies.

Prompt›What is inflation?

GPT-5.3

Inflation is the sustained rise in the general price level of goods and services over time. It reduces the purchasing power of money and is typically reported as an annual percentage change.

Main types

Demand-pull — too much money chasing too few goods.
Cost-push — rising production costs pass through to prices.
Built-in — wage–price spirals become self-reinforcing.

How it's measured

Consumer Price Index (CPI)
Producer Price Index (PPI)
Core inflation (excludes food & energy)

1-click Mindmap

Text is a terrible way to understand complex ideas

Turn any answer into an interactive Mindmap
Instantly see how ideas connect

Highlighter + Notes

Great Research Is Pointless when Insights Get Buried

Highlight the juicy parts in AI answers
Add your own thoughts next to them
Jump back to the exact spot anytime
Your future self will thank you. Trust us.

AI Research Evolution

What are the key trends in AI research concentration?

GPT-5.4

Recent studies show rapid consolidation. Between 2018 and 2023, concentration in AI research has nearly doubled.

Growth has been driven by a handful of labs, on the assumption that compute scales linearly with capability — which may not hold.

The downstream effects compound across jurisdictions and are difficult to isolate in a single framework.

Does compute really scale linearly with capability?

GPT-5.4

This remains one of the most contested premises in the field. The scaling laws held well through GPT-4, but on the assumption that compute scales linearly with capability — a claim the last two years of empirical data have seriously complicated.

Diminishing returns at the frontier are real. Most researchers privately acknowledge this.

What regulatory risks should I flag in my report?

GPT-5.4

Most existing frameworks were designed for earlier technology paradigms. This creates a new class of regulatory risk that few are tracking.

Cross-border enforcement, liability attribution, and compute governance are all substantially underspecified right now.

Thread Notes

This stat is huge — anchor the intro with it.

Wait, is this assumption actually true? Verify before citing.

Thread to pull on later: regulatory angle is underrated.

Click any thought to jump back →

And that's just the start

Six more reasons
to never go back.

Every one of these exists because we asked power users what ChatGPT was missing. Then we built it.

Chat with YouTube

Watch a 2-hour video in 30 seconds

Paste any link. Query the transcript, the comments, the key moments — like it was a document.

Multiple Deep Researches

Run 3 deep researches at once

Fire deep research requests to OpenAI, Gemini, and Perplexity in parallel. Compare outputs instantly and move with confidence.

Prompt Assist

Write prompts like a pro

A dropdown of power phrases drops into your prompt in one tap. Better inputs, better answers — no prompt-engineering degree required.

Lite Threads

Side-quests without leaving main thread

Quick clarifications pop up as mini-chats. Your main thread stays clean, your focus unbroken.

Conversation Index

A table of contents for your chat

Jump across a 100-question conversation in a single click. Long threads stay easy to navigate.

Open in New Window

Compare answers side-by-side

Pop any two answers into their own windows. Stop scrolling up and down — synthesize them in a single glance.

The verdict from people
who try every AI tool.

Reviewers who've seen every AI launch. Builders who ship AI products themselves. Here's what they said.

Considering that ChatGPT and Claude are targeting median user needs, Mnemosphere is the doctor's scalpel to the ordinary person's butter knife.

Chris Messina

#1 Hunter on Product Hunt · Inventor of the Hashtag

The multi-model threads are genius — I always end up juggling tabs just to see how Claude and ChatGPT would answer differently. Love how you’re making messy research actually manageable.

Cruise Chen

Co-Founder, Agnes AI

Mnemosphere sounds like a game changer for anyone who thrives in deep research. The features like instant mindmaps and multi-model threads seem perfect for untangling complex topics.

Alex Cloudstar

Founder, CoLaunchly

Your unfair advantage. Priced for leverage.

Pays for itself the moment you out-compete the masses.

Pro

per month

Get your Pro plan

14-day money-back guarantee

Access to all frontier models

Multimodel Chat

Parallel Prompts

Instant Mindmaps

Inline Highlighter + Notes

Critique

Youtube Video Intelligence

Up to 200 messages / mo

Recommended

Ultra

per month

Unlock the full Mnemosphere

14-day money-back guarantee

Everything in Pro, plus:

Multi-Model Deep Research

Pro Mindmaps

Lite Threads

Up to 1000 messages / mo

Personalized support

First access to experimental features

Already have an account? Log in to manage your subscription.

FAQs

Which models do you support?

Every frontier model, the moment it ships. No swapping subscriptions when a new flagship drops.

Flagship models

GPT-5.5Claude 4.6 SonnetGemini 3.1 ProGrok 4.2Perplexity Sonar

Reasoning models

OpenAI o3Claude Opus 4.7 (Extended Thinking)DeepSeek R1

Is there a free plan?

Why not just use ChatGPT, Claude, or Gemini?

What files can I upload?

How does multi-model streaming work?

Ask once. Watch up to 3 frontier models answer in parallel, side-by-side.

Pick your mix. Choose any 3 models to answer your prompt.
Swap anytime. Add, remove, or switch models mid-conversation — even on a thread that started with just one.
Follow up freely. Every selected model responds to every follow-up.
Cross-model awareness. Each model knows exactly what other models said, so you can ask questions like “GPT, what do you think of Gemini's answer?”

Do you support web search for real-time answers?

Can I generate images or videos?

Do you train models on my data?

Do you have an Enterprise plan?

1B people use ChatGPT.
You need an unfair advantage.

The best models of every AI lab — under one roof.

Cherry pick the best lines from each model.
Build the ultimate answer.

Fire multiple prompts at once