Highlyt now syncs your Kindle highlights automatically

If you read on a Kindle and you've ever wanted to do something useful with your highlights, you already know the problem. They're stuck. The notebook page on read.amazon.com lets you look at them. Your Kindle device lets you make them. Nothing in between connects them to the rest of your reading life.

Today we shipped Kindle auto-sync. Install the Highlyt Chrome extension once, and supported Kindle highlights show up in your Highlyt library while you browse. Same place as your PDFs, your web clips, your YouTube transcripts. Searchable across books. Linkable across ideas. Exportable to Claude or ChatGPT through MCP.

Here's exactly what shipped, why we built it the way we did, and how to get your highlights moving in the next ten minutes.

What auto-sync actually does

You sign in to your Amazon account in Chrome the way you normally would. You install the Highlyt extension and connect it to your Highlyt account once. After that, every six hours while you're using Chrome, the extension quietly opens read.amazon.com/notebook in a background tab, scrapes your highlights, and posts them to your Highlyt library. It closes the tab when it's done. You don't notice it happening.

When new highlights show up since the last sync, you see a small green count on the extension icon: 3, 7, whatever's new. Click the popup and it tells you what arrived. No badge spam, no popups stealing focus, no email digest. The number is there if you want to look at it. If you don't, your library just quietly fills up.

You can also click Sync now any time. The first sync after you install pulls everything you've ever highlighted on Kindle. Subsequent syncs only pull what changed. A re-sync of an unchanged library does nothing visible because nothing's new.

Three ways in, not one

We shipped three import paths, not just the extension, because no single path covers every reader. Here's when to use which:

Browser extension (recommended)

Best for: you read on Kindle, you use Chrome, you want zero ongoing effort. Install once, forget it exists, watch your highlights appear. Works for read.amazon.com, read.amazon.co.uk, .de, .fr, .es, .it, .nl, .com.br, .com.mx, .ca, .com.au, .in. Japan and China are deferred to v2.

My Clippings.txt upload

Best for: you have side-loaded books (personal PDFs sent to Kindle, books from non-Amazon sources), or you don't want to install an extension. Connect your Kindle via USB, dragMy Clippings.txt off the device, drop it into Highlyt's import modal. Works offline, supports German and Spanish notebook locales, deduplicates on re-upload so you can run the same file twice safely.

Bookmarklet

Best for: trying it out without installing anything. Drag the bookmarklet to your bookmarks bar, visit a Kindle book's notebook page, click. That book's highlights land in Highlyt. One book at a time, no ongoing sync. Good for kicking the tires.

The boring infrastructure choices that matter

Most "import your highlights" features ship as a one-time CSV upload. That's the easy version. We made three choices that cost more engineering effort but matter for whether this actually works in your reading life over the long run.

Three layers of dedup

If you re-sync the same book twice, or if Amazon's notebook page returns the same row twice (which happens), you get exactly one copy of each highlight in Highlyt. Not because we deduplicate at the upload step, but because we deduplicate at three independent layers: the parser drops duplicates within a single payload, the document layer merges new highlights into existing books instead of creating a second copy of the book, and the database itself rejects duplicate inserts via a partial unique index. Any one of those catches what the other two miss.

Why three layers? Because data integrity bugs are silent. By the time you notice you have two copies of Thinking, Fast and Slow in your library, the damage is everywhere and the fix means manual cleanup. Defense in depth costs more upfront and saves you from that conversation entirely.

Your Amazon password never leaves your browser

The extension reads from read.amazon.com only. It doesn't have access to your purchases, your payment methods, your address, your account settings. It needs your Kindle session cookie to open the notebook page, and that cookie stays on your device. The extension sends your highlight text to Highlyt's backend, with your Highlyt account JWT in the Authorization header. It does not send your Amazon credentials, ever.

The Chrome Web Store listing reflects this. The host permissions are only the read.amazon domains. There's no <all_urls> grab, no analytics injection, no tracking pixel. We don't want your Amazon data and we made sure we couldn't ask for it even if we wanted to.

Honest sync language

We don't promise "syncs every 24 hours." Chrome's chrome.alarms API doesn't fire when the browser is closed, so any product that promises a strict interval is lying to you about what's possible. We promise "syncs automatically while you browse." If you open Chrome once a day, you get one sync a day. If you live in Chrome, you get four. If your laptop is closed for a week, you sync when you open it.

You can always click Sync now to bypass the schedule.

What you can do with Kindle highlights once they're in Highlyt

The point of getting Kindle highlights out of Amazon's notebook isn't to look at them in a different app. It's to do things with them you couldn't do before. Three workflows that need your highlights to be in a structured, searchable, connected library:

Search across every book at once

Amazon lets you search within one book at a time. Once your highlights are in Highlyt, you can search for "decision making" and pull every passage from every book where you highlighted that idea. The first time you do this, you find connections you forgot you'd noticed. Highlyt's full-text search works the same way for Kindle highlights as it does for PDFs and web clips, because they all index into the same search index.

Link ideas across books with semantic colors

Color the highlight from Thinking, Fast and Slow blue for "key concept." Color the related example from Predictably Irrational blue too. Now they're searchable together. Semantic color-coding turns a flat pile of highlights into something you can navigate by meaning instead of by book.

Then create a link between them in Highlyt's knowledge graph. Now when you write or research, you can pull both up together with one query.

Feed structured highlights to Claude or ChatGPT

This is the workflow that didn't exist before. Highlyt's MCP server exposes your highlights to AI tools as structured data, not pasted text. Ask Claude "what did Kahneman say about base rates?" and it pulls the actual highlight with the book, page, color label, and any notes you added. Your AI gets context. Your reading gets used.

For Kindle highlights specifically, this matters because Kindle gives you no native way to preserve the meaning and relationships around what you marked. Readwise now has MCP too, so MCP alone is not the gap. Highlyt's gap is the structure around the highlight: semantic color meaning, graph links, source metadata, and notes in one AI-readable context layer.

How to get started in five minutes

Create a Highlyt account at highlyt.app if you don't have one. Seven-day free trial, no credit card.
Install the Highlyt Chrome extension. The link is in your library under Import → Kindle.
Click the extension icon, sign in to Highlyt. The popup shows "Connected as [your email]" once it's linked.
Make sure you're signed in to read.amazon.com. The extension uses your Amazon session cookie to read your notebook.
Click Sync now in the popup. Wait 30-90 seconds for the first sync. Your Kindle books appear in your Highlyt library with a Kindle badge.

Open one of them. You'll see the cover, the title, your highlights with their colors, any notes you added on Kindle, and a deep link back to read.amazon.com if you want to find a passage in context. From there, every Highlyt feature works the same way it does for PDFs: search, color-code, link, export.

What's not in v1

A few things we deliberately deferred so we could ship cleanly:

Japan and China. read.amazon.co.jp and read.amazon.cn use different DOM structures and we haven't built region-specific scrapers yet. Other Kindle services (Readwise) document the same incompatibility.
Audible highlights. Audible doesn't expose highlights via the notebook page. Different ingestion path, different scope.
Kindle Scribe handwritten notes. Stored separately from text highlights. Worth doing, not in this release.
Auto-merging clippings.txt and extension imports of the same book. If you upload Thinking, Fast and Slow via clippings.txt and also have it synced via extension, you'll see two documents. Fuzzy title+author matching is a v2 feature.

Try it

If you've been waiting for a clean way to get your Kindle reading into a graph of ideas you can actually search and connect, this is it. Sign up for Highlyt, install the extension, and watch your reading start working for you instead of sitting in a notebook page nobody opens.

And if you want to understand the bigger picture of why exporting Kindle highlights matters at all, read the full Kindle highlights guide next.