Key Takeaways
The Google Translate extension no longer translates entire pages. Chrome handles full-page translation natively, so there’s nothing to install.
DeepL’s free extension translates selected text. Full-page translation, automatic page translation and glossaries require DeepL Pro.
Most translation extensions send the text you translate to a server. If you need to keep it on your device, consider Firefox’s built-in translator or Linguist in offline mode.
A translation popup disappears, but the words you looked up are easy to forget. Language-learning tools such as WordByWord, Readlang and Language Reactor let you save words and review them later.
The best translation extension depends on how you use it. The comparison below covers the main options, followed by a closer look at what each one offers.
What are the best translation extensions right now?
Prices, usage limits and supported languages change regularly, so check each extension’s store listing before installing it.
Extension | Best for | What it does | Free vs paid | Saves words for learning | Browsers |
|---|---|---|---|---|---|
Learning vocabulary from websites, YouTube and PDFs | Translate selected or double-clicked words, save them with their sentences and sources, use Spotlight, read clickable YouTube subtitles and open PDFs in its own viewer; 50+ languages | Translation and audio are free; Premium removes limits on training sessions and AI features | Yes | Chrome | |
Chrome built-in | Reading a page in another language | Translate entire pages or selected text from the right-click menu | Free | No | Chrome |
Google Translate extension | Quick phrase lookups | Translate highlighted text in a popup; no full-page translation | Free | No | Chrome |
DeepL Translator | Translating selected text | Translate selected text; full-page translation, automatic page translation and glossaries with Pro | Free with a monthly character limit / Pro | No | Chrome, Edge, Firefox |
Immersive Translate | Bilingual pages, subtitles and PDFs | Display original and translated text side by side, translate subtitles, PDFs and ebooks, and choose from 20+ translation engines | Free with daily limits / Pro | No | Chrome, Edge, Firefox, Safari (Mac) |
Linguist | On-device translation | Built-in offline translation, optional cloud services and open-source code | Free | Personal dictionary, but no review system | Chrome, Firefox |
Language Reactor | Learning through Netflix and YouTube | Dual subtitles, popup dictionary and playback controls | Free / Pro | Yes (Pro) | Chrome (desktop) |
Readlang | Learning through reading | Translate words and phrases on web pages, create spaced-repetition flashcards and export to Anki | Free (10 phrase translations a day) / Premium | Yes | Chrome |
What each extension actually does
WordByWord: for keeping the words you look up
Select a word or double-click it, and a popup appears with up to ten meanings and pronunciation. You can rate how well you know the word on a scale of 1 to 5. It’s then saved along with the sentence it came from and a link back to the original source, whether that’s a web page, a page in a PDF or a moment in a video. There’s no need to save it separately or copy it into a flashcard app.
Spotlight makes it easier to recognise familiar words as you read. It highlights words in different colours according to your vocabulary: blue for words you haven’t learned yet, orange for words you’re still learning, and no colour for words you already know. If you saved a word last week, you’ll see it highlighted when it appears in a new article or subtitle. WordByWord also shows how much of a page or video you already understand and which new words would make the biggest difference.
On YouTube, WordByWord replaces the standard captions with its own clickable subtitles. Click a word to pause the video and open the same translation popup. PDFs open in WordByWord’s own viewer, including files stored on your computer.
Your saved words are stored in your vocabulary on wordbyword.io. You can practise them on the website, where words move up as you answer correctly. You can also export your vocabulary to Anki, CSV or PDF.
WordByWord isn’t a full-page translator, so you’ll still want to use Chrome’s built-in translation when you need to read an entire page in your own language. The extension supports 50+ languages and works in Chrome, but it doesn’t support Netflix yet. Translation and audio are free and unlimited; saving words and using Spotlight require a free account. Premium removes the monthly limits on training sessions and AI features and adds HD voices.
Quick verdict: A good starting point if you’re learning a language and want to keep track of the words you look up.
Chrome’s built-in translation: nothing to install
Chrome can offer to translate a page when it’s written in a language you don’t read. You can also translate selected text from the right-click menu. The page text is sent to Google Translate’s servers.
Other browsers have their own built-in options. Edge uses Microsoft’s cloud-based translator, while Firefox’s built-in translation runs on your device without sending the text elsewhere.
None of these built-in translators keeps a record of the words you look up.
Quick verdict: All you need if you want to read a page once and move on.
Google Translate extension: for selected text
The Google Translate extension no longer translates entire pages; that feature is now built into Chrome. The extension is designed for shorter lookups: highlight or right-click text to translate it in a small popup. You can also set it to translate text as soon as you select it. For non-Latin scripts, it offers romanisation as well.
The extension is free, and the text you translate is sent to Google.
Quick verdict: A convenient way to look up a phrase without leaving the page.
DeepL Translator: free for selected text, Pro for pages
DeepL’s extension translates selected text for free, subject to a monthly character limit. If you want to translate entire pages, enable automatic page translation or use glossaries, you’ll need DeepL Pro. The extension is available for Chrome, Edge and Firefox.
The extension’s store listing mentions more than 30 languages. In November 2025, DeepL announced around 70 additional languages, bringing the total to over 100. The new languages were initially available in beta to business customers. Many users prefer DeepL for European language pairs, but we haven’t tested its accuracy ourselves. If translation quality matters to you, try it alongside Google Translate on a few paragraphs in your language pair.
Quick verdict: Worth trying for selected text. If you need full-page translation, expect to pay for Pro.
Immersive Translate: support for multiple content formats
Immersive Translate displays the original text and its translation side by side on a web page. It also offers bilingual subtitles on YouTube, Netflix and other video platforms, as well as translation for PDFs and ebooks.
You can choose from more than 20 translation engines, including DeepL, OpenAI and Gemini. The text you translate is sent to the provider you select.
The free plan has daily usage limits and supports standard PDFs. Scanned PDFs, formula recognition and premium AI models are available on paid plans. The extension works with Chrome, Edge, Firefox and Safari on Mac, and mobile apps are available too.
Quick verdict: A strong option if you regularly translate different types of content, from web pages to videos and documents.
Linguist: translation on your device
Linguist is an open-source extension with a built-in offline translator. When you use offline mode, your text stays on your computer. You can also connect to services such as Google, Bing and DeepL, but in that case your text is sent to the selected provider.
Offline mode supports fewer languages than cloud-based services. Linguist is available for Chrome and Firefox.
Quick verdict: Worth considering for confidential text, provided you use offline mode.
Other extensions for language learners
WordByWord isn’t the only extension that combines translation with language learning.
Language Reactor offers dual subtitles and a popup dictionary for Netflix and YouTube. Saving words is part of its Pro plan, and the extension works in desktop Chrome. Readlang focuses on reading: it translates words and phrases on web pages and turns them into spaced-repetition flashcards, with support for Anki export. Rememberry lets you save words as flashcards and highlights them on the pages you visit.
The best choice depends on what you spend most of your time doing. If you mainly watch Netflix, Language Reactor may be a better fit. If you read articles and PDFs, watch YouTube and want to keep all your vocabulary in one place, WordByWord is worth a look.
How do you choose the right translation extension?
A few questions can help you narrow down the options.
What do you want to do after translating? If you just need to understand a page, Chrome’s built-in translator is probably enough. If you want to remember the words you look up, choose WordByWord or another language-learning tool. For bilingual subtitles and PDFs, Immersive Translate is worth considering.
Does it support your language pair? Language coverage varies between extensions. Check the supported languages before installing anything, and compare the results on a paragraph you already understand well.
Where does your text go? Most extensions send translated text to a server, either their own or a provider such as Google, Microsoft, DeepL or OpenAI. How the text is stored, how long it’s retained and how it’s used depends on the provider’s privacy policy and may also vary by plan. If you need to keep text on your device, consider Linguist in offline mode or Firefox’s built-in translator.
What permissions does it request? Translation extensions often ask for permission to “read and change all your data on all websites” because they need to work across different pages. That permission can be necessary for their functionality, but it’s still worth checking who developed the extension and whether the developer has a clear privacy policy. In the Chrome Web Store, look at the “Privacy practices” section, developer details and last update date.
Why language learners need more than a translator
Most comparison articles focus on translation accuracy and support for different formats. That makes sense if you only need to understand a document once. But if you’re learning a language and regularly read articles or watch videos in it, there’s another question to consider: what happens to the words you look up?
Without a way to save them, you may end up translating the same word over and over. The usual workaround is to copy each word, its translation and an example sentence into a separate flashcard app. That takes time, and it’s easy to abandon the habit after a few days.
It’s more practical when looking up a word also lets you save it with its context, so you can get straight back to reading. You don’t have to turn every unfamiliar word into a flashcard, either. Save the ones you want to learn and come back to them later.
Try WordByWord on the next page you read
Install the extension from the Chrome Web Store and create a free account. Then open an article or YouTube video in the language you’re learning, double-click a word you don’t know and rate how well you know it.
Turn on Spotlight to see your saved words highlighted when they appear again on other pages. You can practise your saved vocabulary on wordbyword.io.
Get started at wordbyword.io/extension.
