Caption.IM

Caption.IM is a privacy-first AI captioning assistant designed specifically for macOS. It transforms any audio on your Mac into real-time captions, instant translations, recordings, and structured meeting notes, all powered locally on your device. Unlike browser extensions or meeting bots that require integration with specific platforms, Caption.IM captures system audio directly, allowing it to work across virtually any application. This includes popular video conferencing tools like Zoom, Google Meet, and Microsoft Teams, as well as media platforms such as YouTube, online courses, podcasts, livestreams, webinars, and recorded videos. The product is built with local AI and Local LLMs in mind, ensuring that your conversations remain private while significantly improving productivity, accessibility, and information equity. There are no bots joining your meetings, no browser dependency, and no complicated setup required. Caption.IM is optimized for Apple Silicon (M1, M2, M3, and later) to deliver ultra-fast speech recognition with minimal latency and efficient power usage. It serves a wide audience including remote workers, online learners, multilingual teams, accessibility advocates, content creators, researchers, and students who need to turn any conversation into searchable, translatable knowledge instantly.

Real-Time Transcription

Caption.IM generates live captions for any audio source on your Mac. Whether you are in a video meeting, watching a recorded lecture, or listening to a podcast, the application provides accurate, real-time subtitles that appear as the audio plays. This feature is powered by local AI processing, ensuring low latency and high accuracy without sending your data to external servers. The transcription engine is optimized for Apple Silicon, delivering fast performance that keeps up with natural conversation speeds.

Instant Translation

Understand content in multiple languages with real-time translated subtitles. Caption.IM can translate audio from one language into another as it plays, displaying the translated text in a floating subtitle window. This feature is invaluable for multilingual teams, international meetings, and learning from foreign language content. The translation engine works alongside the transcription engine, providing a seamless experience where you can see both the original text and the translation simultaneously.

Floating Subtitle Window

Caption.IM features an elegant, transparent overlay that works seamlessly with macOS. This floating subtitle window can be positioned anywhere on your screen, allowing you to view captions while working in other applications. The design is unobtrusive and customizable, ensuring that the subtitles do not interfere with your workflow. The window supports transparency and can be resized to suit your preferences, making it ideal for use during video calls, presentations, or while watching videos.

AI Meeting Summaries

After capturing audio from a meeting, conversation, or lecture, Caption.IM automatically generates structured summaries and key insights. This feature transforms long discussions into clear summaries, key points, action items, and even mind maps. The AI analysis is performed locally on your device, preserving privacy while providing valuable post-meeting documentation. Users can quickly review what was discussed, identify important decisions, and track assigned tasks without needing to replay the entire recording.

Remote Meetings and Virtual Collaboration

For professionals working remotely, Caption.IM provides real-time captions for all video conferencing platforms including Zoom, Google Meet, and Microsoft Teams. This ensures that every participant can follow the conversation, even in noisy environments or when dealing with audio quality issues. The AI meeting summary feature then automatically generates notes, action items, and key points, saving time and ensuring nothing is missed. This is particularly useful for team members in different time zones who may need to catch up on missed meetings.

Online Learning and Education

Students and educators can use Caption.IM to generate live subtitles for online courses, webinars, and recorded lectures. This improves comprehension for all learners, especially those who are non-native speakers or have hearing impairments. The ability to record and generate summaries allows students to focus on understanding during the lecture rather than taking detailed notes. Later, they can review the AI-generated summaries and key points to reinforce their learning and prepare for exams.

Multilingual Team Communication

In global organizations where team members speak different languages, Caption.IM bridges the communication gap with real-time translation. During meetings, participants can view translated subtitles in their preferred language, ensuring everyone understands the discussion. This feature eliminates the need for separate translation services or interpreters, making international collaboration more efficient and inclusive. The local processing ensures that sensitive business conversations remain private and secure.

Accessibility for Hearing Impairments

Caption.IM provides a powerful accessibility tool for individuals who are deaf or hard of hearing. By generating real-time captions for any audio on the Mac, it ensures that all content is accessible, from live meetings to recorded videos and podcasts. The floating subtitle window allows users to position captions where they are most comfortable, while the local processing ensures that no personal conversations are transmitted over the internet. This makes Caption.IM a reliable and privacy-conscious solution for workplace and personal accessibility needs.

Does Caption.IM work with any application on my Mac?

Yes, Caption.IM captures system audio directly, which means it works with virtually any application that produces sound. This includes video conferencing tools like Zoom, Google Meet, and Microsoft Teams, as well as web browsers playing YouTube or online courses, media players for podcasts and videos, and even system sounds. There is no need for browser extensions or application-specific integrations.

Is my audio data sent to the cloud or external servers?

No, Caption.IM is built with a privacy-first approach. All speech recognition, transcription, translation, and AI summarization processes run locally on your Mac using local AI and Local LLMs. Your conversations never leave your device, ensuring that sensitive meeting discussions, personal calls, or confidential information remain completely private and secure.

What are the system requirements for Caption.IM?

Caption.IM requires macOS 15.6 or later and is optimized for Apple Silicon (M1, M2, M3, and later chips). The application is designed to deliver ultra-fast speech recognition with minimal latency and efficient power usage on these processors. The app size is approximately 18.1 MB, and it is available in English from the Mac App Store.

Can I use Caption.IM for recording and later review?

Yes, Caption.IM includes recording capabilities that allow you to capture important audio from meetings, lectures, or conversations. After recording, the application can automatically generate structured summaries, key points, action items, and mind maps. This makes it easy to review and reference important discussions without needing to replay the entire audio file.

Caption.IM is available as a free download on the Mac App Store with in-app purchases. The application is categorized as Productivity software and is available for macOS 15.6 or later. Subscriptions automatically renew unless canceled at least 24 hours before the end of the current billing period. For specific pricing details on subscription plans and in-app purchase options, please refer to the application listing on the Mac App Store or visit the official website at caption.im.