About SmileSub
We do one thing: help Chinese-language video cross the language barrier. Translate between 20 languages including Chinese, English, Japanese, and Korean, and burn bilingual subtitles into a finished file — the video itself never leaves your computer, and there is nothing to install.
Our mission
Video content is exploding, and subtitles are no longer an optional extra — they are how you make content accessible and reach a wider audience. Yet the traditional way of producing subtitles is slow and laborious.
SmileSub exists to change that. Using leading speech recognition and smart translation, we turn a complicated subtitle workflow into a few minutes of easy work, so any creator can add professional subtitles to their own videos.
Built to serve every user
We believe technology should serve people: make hard things simple, and put professional tools within everyone’s reach
What we build on
A state-of-the-art AI stack, used to produce high-quality subtitles for you
Cloud recognition + local burn-in
Speech recognition and translation run in the cloud, so you do not need a powerful computer; the burn-in step runs inside your browser, and the video itself does not have to be uploaded to a server. Target languages currently cover 20 options including Chinese, English, Japanese, and Korean.
Brand-term locking
The worst problem with machine translation is not a clumsy sentence — it is your brand and product names coming out wrong. Upload a glossary and those terms keep exactly the wording you specify, consistently, instead of a different translation in every line.
Fast processing
Multithreaded, concurrent processing gets subtitle generation done efficiently. It is fast, which cuts down your waiting time.
Data safety
Burn-in happens in your browser and the video itself does not have to be uploaded; cloud traffic is encrypted end to end and temporary files are cleaned up automatically. Your video content and the subtitles generated from it are strictly protected and are never used for any other purpose.
Pro editing
Preview subtitles, review the text, and export. Export standard formats such as SRT and VTT that are compatible with mainstream video editors.
Works on any platform
Use it directly in the browser with no software to install. Reach your subtitle tasks from anywhere and manage your recognition history.
Milestones
From an idea to a real product — how we grew
Project started
The team saw how painful traditional subtitle production was and decided to build a smart subtitle tool for creators taking their video global. Two engineering principles were set early: use mature cloud services for recognition and translation to guarantee quality, and run the burn-in inside the user’s browser to keep server costs down.
Technical breakthrough
We integrated several language models and achieved high-accuracy cloud speech recognition. We also built a smart sentence-splitting algorithm that greatly improved subtitle readability and the viewing experience.
Public beta
We released the beta and invited early users to take part. Their feedback drove continuous improvements to the product and the experience, in preparation for general release.
General release
SmileSub went live, providing professional subtitle generation for video creators. We keep iterating, aiming to become a leading AI subtitle generation platform.
Contact us
Every user’s voice matters to us — we would love to hear your ideas and suggestions
Email us
xiaoxiekeke@qq.com
Support hours
We reply 9:00–18:00 on weekdays
Help docs
Detailed usage guides