Highlight Reader: read-aloud that highlights the page as it reads

A Chrome extension that reads any web page aloud and highlights each sentence where it is, on the page, not in a side panel. The extension is free and already published; this page is about a paid add-on that is not finished: half of it is built but switched off in the version under review, and the other half has no supplier yet.

What it does

• Select text, or press one key, and it reads from there in a natural voice.
• The sentence being read is highlighted on the page itself, so your eyes and ears stay in the same place.
• Speed, voice and highlight colour are three clicks away. Nothing is behind a login.

Why this, why now

Several popular readers recently moved reading into a side panel, and the on-page highlight went with it. People asked for it back. This extension is built around that one thing: the highlight stays on the page.

What it is not

Not a subscription, not an app you sign up for, not a PDF studio. It reads web pages. If a free reader already does what you need, keep it — we would rather say that here than after you have paid.

What it cannot read

Text inside a cross-origin <iframe> — an embedded document served from another site, which is how some online viewers and comment widgets are built — is skipped, and skipped silently: you hear the rest of the page and nothing tells you a paragraph was left out. Same-origin frames and open shadow roots (one way web components are built) are read as of version 1.0.1, the version on the store today. If the pages you care about embed their text from another site, this extension is not for you yet, and we would rather you find that out here than after paying.

What the payment covers — and what is already free

The voices are free. Chrome ships its own text-to-speech, including network voices that sound natural, and the extension uses them at no charge. We are not selling you a voice you already have.

What a paid add-on would add is word-level highlighting together with a natural voice. On our test machine the voices Chrome hands an extension report only the start and end of each utterance: we checked all nineteen of Chrome’s own network voices and the 13,363 voices the system’s speech engine adds on top of them, and not one reports a word or sentence boundary — so a highlight built on them moves a sentence at a time. That machine runs Linux, and we have not measured this on Windows or on a Mac. As far as we can tell the gap is in Chrome’s Linux speech layer rather than in the voices themselves, which means your own voices may report word timings if you are on Windows or macOS — and if they do, the word-level highlight is already exact on your machine with a free voice, and the first of the three things listed below is not something you need to pay us for. We would rather you read that before paying than work it out afterwards. A word-level highlight here therefore has to get its timing from somewhere else: from a paid cloud voice that returns per-word timings, or — where those timings are not available — estimated from sentence length and speaking rate. Since first writing this we have built the estimated half and measured it on twelve sentences against two different local speech engines. On the first, the highlight ends up a median of 0.42 words from where the word actually starts; on the second — same machine, same twelve sentences, a different way of synthesising speech — the median is 1.12 words, close to three times worse. On their worst sentence they were seven and six words out. We print both numbers rather than the better one, because the gap between them is the honest size of the uncertainty: how far the estimate drifts depends on the voice, and we have not measured it on the paid cloud voice this would actually use. That code is not on the store yet — version 1.0.1, the one you can install today, still highlights a sentence at a time, and in the 1.0.2 we have submitted for review the word-by-word code is present but switched off, because we would rather ship it with a voice that makes it exact than ship a drifting highlight as if it were the finished thing. The other half, a paid cloud voice that returns per-word timings, we still have not run end to end. One payment of $4.99 would buy 150,000 characters of cloud narration — about 25,000 words, a short book — read whenever you like within twelve months. That is the whole of it: a ceiling, not a monthly allowance, and not a subscription. What it buys you:

• a highlight that follows each word rather than each sentence — exact where the voice reports word timings, estimated from the speaking rate where it does not, which means it can drift;
• no pause between sentences (with the free voices, each sentence is a separate utterance, and you hear the join);
• more languages than your machine happens to have installed.

What the two highlights look like

The two lines below are drawn by this page in HTML. They are an illustration of where the highlight sits — not a screenshot and not a recording of the extension. The first line is what version 1.0.1, the one on the store today, does; the second is what the add-on would do where the voice reports word timings. Nothing here plays audio, and the drift described above is not drawn: a still picture cannot show it.

Cloud voices bill us per character, so that 150,000 characters is a real ceiling rather than a formality, and we would rather print it next to the price than discover it together later. No automatic renewal. Sentence highlighting and Chrome’s own voices stay free after the twelve months, for good.

Price and terms

$4.99, one payment, now, for the paid add-on — not for the extension, which is free. Nothing more is due when it ships. No date is promised: you get one email when it ships.

Full refund, no questions, at any time before delivery. Email support@rehobothbuilds.com with the word “refund” — you do not owe us a reason, and we do not ask for one. If we decide not to build it, we refund everyone without being asked and say so publicly on this page. You are not taking a risk we are not taking.

Pre-order for $4.99

Not ready to pay?

Leave an address and we will tell you when it ships — and nothing else. No newsletter, no sequence, one message.

One thing worth saying plainly, because it is how we actually decide: pre-orders are the only signal that decides whether we finish this. Not whether we start it: one half is already written and switched off, and the other half has no supplier yet, so what a pre-order decides is whether we turn the first one on and open an account for the second. Addresses on this list are not counted in that decision — we read them as interest, not as demand. Waiting costs you nothing today, but it is not free: pre-orders are the whole threshold — a page with no pre-orders is a page we stop working on. If you wait, you are betting that a stranger pays. We are telling you this so that a quiet list does not get read as a verdict on the idea, and so that nobody waits for something that never gets finished.

Would you pay $4.99 once for this? (optional) Yes, that's fair Maybe, but cheaper Maybe, if it also did something else No, a free one is enough for me No, I don't need this Tell me when it ships

We store the address and the date. Nothing else, and it is not shared. Reply to the one message you get and we delete it.

That is what this page stores. What the extension itself stores, once you install it, is in its privacy policy — readable before you pay.