The Mac Had a Summarizing Tool Two Decades Before AI Made It Cool

March 21, 2026

A few weeks ago, while cleaning up my keyboard settings on macOS, I stumbled on a checkbox I had long forgotten: "Summarize." Curious, I re-enabled it, selected a long article in Safari, right-clicked, and there it was: Services → Summarize. A small window appeared, offering to condense the page into a handful of sentences, with a slider to control just how short I wanted it. No login, no AI, no spinning "thinking" indicator. Just instant, offline text reduction.

It turns out this feature has been sitting inside macOS for roughly 25 years, mostly ignored, while the rest of the industry raced to reinvent the exact same idea with large language models.

A Relic From the Early Days of Mac OS X

The Summarize service traces back to the earliest years of Mac OS X, reportedly appearing as far back as 2001. It lives inside the Services menu, a system-wide feature that lets one application borrow small functions from another (spell-checking, dictionary lookups, or, in this case, text summarization) without the user ever leaving the app they're working in.

The Services menu itself has an even older lineage. It originated in NeXTSTEP, the operating system built by Steve Jobs's company NeXT in the late 1980s, which Apple acquired in 1997 and which became the foundation of Mac OS X. When Apple engineers rebuilt Mac OS X on top of NeXTSTEP's architecture, the Services concept came along for the ride.

For years, though, the menu was more confusing than useful. Most of its entries were greyed out, undocumented, and scattered across dozens of apps, so people mostly ignored it. That changed somewhat with Mac OS X Snow Leopard in 2009, when Apple reorganized the Services menu and gave users a proper way to enable, disable, and assign keyboard shortcuts to individual services from System Preferences.

How It Actually Works

Unlike ChatGPT, Gemini, or Apple Intelligence's writing tools, Summarize isn't generative AI. It doesn't write new sentences to describe your text, it extracts existing ones. The tool analyzes the selected text, scores each sentence or paragraph for how central it seems to the overall meaning, and then keeps only the highest-scoring pieces, discarding the rest.

This approach is a classic technique in natural language processing called "extractive summarization," as opposed to the "abstractive summarization" used by modern AI models, which paraphrase and generate new text. Apple has never published detailed documentation on the exact algorithm behind the Mac's implementation, and the results can feel a bit mysterious, but the underlying idea is well understood in the field: rank sentences by importance, then trim.

Once enabled, (via System Settings → Keyboard → Keyboard Shortcuts → Services → Text → Summarize) the feature works almost anywhere text can be selected: Safari, Mail, TextEdit, Pages, Notes, and even some third-party browsers and email clients. Users can choose between "Sentences" mode, which pulls individual standout sentences out of their surrounding paragraphs, or "Paragraphs" mode, which keeps whole paragraphs intact for more context. A slider lets you dial the summary length anywhere from a one-line gist to nearly the full original text.

Why It Was Forgotten

Part of the reason Summarize never became a household feature is discoverability. It's turned off by default, buried three menus deep, and the Services menu it lives in has always had a reputation for being cluttered and confusing. Unless someone stumbled across a blog post explaining how to enable it, there was little reason to ever find it.

There's also the matter of quality. Extractive summarization is a fundamentally different, blunter tool than what large language models can now do. It can't explain, infer, or reword, it can only cut. A summary of a nuanced argument might read as a strange, disjointed sequence of leftover sentences rather than a coherent overview. That limitation likely kept it a niche trick for power users rather than something Apple ever marketed heavily.

Still Alive, Quietly, Today

Remarkably, the feature hasn't disappeared. It's still present in current versions of macOS, sitting alongside (and largely eclipsed by) Apple Intelligence's newer, AI-driven summarization tools in Safari and elsewhere. The old Summarize service doesn't need an internet connection, doesn't send any data to a server, and doesn't require a supported chip. It just needs to be switched on.

In a moment when "summarize this" almost always means using AI, there's something quietly appealing about a tool that does the same basic job entirely on-device, using nothing more than sentence-ranking logic written decades ago. It's not going to replace an AI summary for a nuanced document. However, for a quick, private, offline gist of a long article, it still gets the job done — and it's already sitting on your Mac, waiting to be turned on.