A second brain
for your browsing

Mnemonic watches what you actually read — not just what you click.
Deep rabbit holes persist. Doom-scrolling fades to nothing.

mnemonic 47 memories · 12 domains
RecentStrongestFading
The Town That Was Buried in Molasses (Twice)
9.5
The Great Molasses Flood of 1919
8.2
Do Octopuses Dream? Scientists Finally Have an Answer
5.8
Can Pigeons Actually Play Ping-Pong?
2.1

History is not a memory

  • A 3am Wikipedia binge and a 20-minute research deep dive look identical
  • Every page you glanced at for 2 seconds is treated the same as one you studied
  • Good luck finding "that article about the thing" from last Tuesday
  • Your history from 2019 sits next to yesterday's — equally useless
  • You can't ask it questions, you can only scroll and pray

Mnemonic knows the difference

  • 14 minutes reading the Molasses Flood wiki? That's a strong memory now
  • Accidentally opened a LinkedIn notification? Gone by tomorrow
  • Revisiting a page right as it's fading gives extra reinforcement
  • Every memory has a strength score you can see decaying in real time
  • Ask "what did I read about vim?" and get actual answers

How it works

01

Just browse

No tagging, no bookmarking, no "save for later" that you'll never open. Mnemonic measures your actual engagement in the background — time on page, scrolling, interaction — and filters out the junk automatically.

02

Watch things fade (or not)

Every page gets a stability score. Spent 14 minutes on that article? It'll stick around for weeks. Bounced after 10 seconds? It's already dying. Come back to something just as it's fading and the reinforcement is massive — that's the spacing effect.

03

Query your own brain

Open the AI chat and ask things like "what was that blog post about database indexing?" Mnemonic searches your memories, finds the match, and when AI references it — the memory gets reinforced automatically.

Features

Real Memory Model

Based on FSRS (the same algorithm behind Anki). Every page gets a stability score that grows with engagement and decays without it. Documentation pages get a bonus. Quick bounces get penalized.

Forgetting Curve

Memories decay on a real exponential curve, not some arbitrary timer. You can watch a page's retrievability drop from 95% to 30% over days — and see exactly when it'll be forgotten.

PRO

AI Chat

Bring your own API key (Claude, GPT, or Gemini) and talk to your browsing history. "What was that CSS grid tutorial?" The AI searches your memories and finds it.

PRO

Obsidian Vault Sync

Every memory becomes a markdown file with full YAML frontmatter — stability, retrievability, visit count, event timeline. Point it at your vault and your second brain writes itself.

Noise Filter

Gmail, Twitter, Netflix, Slack — all blocked by default. Add your own rules with wildcards and path filters. *.reddit.com blocks everything; reddit.com/r/programming blocks just one sub.

Nothing Leaves Your Machine

Your browsing data stays in Chrome's local storage. Period. We don't run analytics, we don't have a dashboard of your habits, we literally can't see what you browse.

Pricing

The core memory engine is free forever. Pro unlocks the good stuff.

Free

$0

forever

  • Full memory tracking & FSRS model
  • Dashboard with Recent / Strongest / Fading
  • Search across all your memories
  • Custom noise filter rules
  • 30-day memory cap
Add to Chrome

The privacy part

We can't see your data

Not "we promise not to look." We architecturally cannot. Your memories live in Chrome's local storage and never hit a server.

No cloud, no sync, no phoning home

The extension makes zero network requests by default. The only time it talks to our server is to check your subscription status. That's it.

Your key, your AI bill

AI chat calls go directly from your browser to the provider (Anthropic, OpenAI, Google). We never see your API key, your prompts, or the responses.

Our server knows two things about you

Your email address and whether you pay us. That's the entire database row. No browsing data, no usage analytics, no tracking pixels.

FAQ

What exactly gets stored, and where?

For each page you visit long enough (30+ seconds of active engagement), Mnemonic saves the URL, title, a text snippet, word count, and engagement data (active time, visit count, events). All of this lives in Chrome's local storage on your device. Our server only knows your email and subscription status.

What's this "stability" and "retrievability" I keep seeing?

Stability is how long a memory lasts before it fades — measured in days. A 5-minute read on documentation might give you 7 days of stability. Retrievability is the probability you'd still recall the page right now. It starts at ~100% and decays exponentially over time. When it gets low enough, the memory is archived or forgotten.

Why does revisiting a fading page help more than revisiting a fresh one?

That's the spacing effect — the same principle behind flashcard apps like Anki. If you come back to a page when its retrievability is at 50%, the reinforcement bonus is much larger than if you come back when it's still at 95%. The model rewards you for retrieving things that are on the edge of being forgotten.

What's the difference between the 30-day and 365-day memory cap?

Free users have memories capped at 30 days of stability. That means even with heavy engagement and multiple revisits, a memory can't persist beyond about a month. Pro users get a 365-day cap, so deeply reinforced pages can stick around for up to a year.

How does the AI chat actually work? Do you see my prompts?

No. The AI chat runs entirely in your browser. When you ask a question, Mnemonic searches your local memories for matches, packages them as context, and sends the request directly to the AI provider (Anthropic, OpenAI, or Google) using your own API key. We never see the request, the context, or the response.

I cancelled Pro. What happens to my memories?

Nothing gets deleted. Your memories stay exactly where they are. You just lose access to the AI chat, vault sync, and advanced tuning. The stability cap drops back to 30 days, so existing memories above that won't grow further — but they won't be forcibly truncated either. Re-subscribe and everything picks up where you left off.

Can I export my data?

Pro users can sync to a local folder as markdown files, which effectively exports everything continuously. Free users can still see all their data in the extension dashboard. We're working on a one-click JSON export for everyone.

Stop losing your mind

You've already forgotten three articles from this week. Mnemonic wouldn't have.

Add to Chrome — It's Free