How to translate a subtitle file online for free?

Upload your subtitle file to SubMorph, select your target language and preferred pacing style, connect your free AI API key, and click 'Translate Subtitles'. The translated subtitle file will be ready for 1-click download with 100% timecode synchronization.

Does SubMorph keep original subtitle timecodes synchronized?

Yes. SubMorph features a deterministic timecode matcher and overlap resolution engine that ensures zero subtitle shifting, preserving 100% frame-perfect synchronization with your video.

Is my subtitle data private and secure?

Yes. All subtitle parsing and processing is performed client-side directly in your browser or local device. No subtitle files are permanently retained on third-party servers.

SubMorph — Free AI SRT Subtitle Translator Online (100% Timing Sync & Fast Pacing)

Engine Settings

Auto-Adaptive

Translate In 85+ Languages

AI Model Selection Awaiting Keys

Subtitle Pacing Fast

Context & Genre Tone Optional

Glance Express 3-Stage

3-Stage Auto: Translate ➔ Condense ➔ 1–4 Words

Need subtitles? Download from:

SubDL OpenSubtitles

Drop your Subtitle file here

Supports SRT, VTT, TTML, ASS, SBV, TXT, JSON, XML, CSV, LRC & more

Need subtitles? Download from:

SubDL OpenSubtitles

Upload a subtitle file and connect your API key in Settings to start.

Translation Completed!

Subtitles localized with 100% timecode integrity

sample.srt

Auto-saved in /Download/SubMorph

Drop video file or click to browse

Any video format • Unlimited file size (100% Offline)

On-Device AI

LiteRT

Gemma 4 E4B • 3.7 GB (Offline)

Offline AI

Model not downloaded or selected

Hugging Face ↗

API Keys

Auto-Failover

Configure Gemini

Get Key (100% Free)

API Base URL / Endpoint (OpenAI Compatible) e.g. https://api.together.xyz/v1, https://api.mistral.ai/v1, or http://localhost:11434/v1

Default Model ID / Name e.g. meta-llama/Llama-3.3-70B-Instruct, mistral-large-latest, or qwen2.5:7b

API Key / Bearer Token Optional: Leave blank for local offline AI (Ollama / LM Studio / LocalAI)

Local AI & Offline Tip: Ollama and LM Studio work without requiring an API key. If connecting to Ollama from web browser, launch it with OLLAMA_ORIGINS="*" ollama serve to enable browser CORS access. On Android APK app, local IP endpoints work directly!

Recommended AI

0/2 Connected

Google Gemini Not Connected

OpenRouter Not Connected

Cloud Subtitle Archive

Subtitles are saved for 3 days

Please sign in to view and access your 3-day cloud subtitle history.

SubMorph — Free AI SRT Subtitle Translator Online (100% Timing Sync)

Engine Settings

Drop your Subtitle file here

Translation Completed!

Drop video file or click to browse

Extraction Complete!

Google Cloud Sync

On-Device AI

API Keys

App Information & Preferences

Cloud Subtitle Archive

Connect to Internet

Update Required

Engine Settings

Drop your Subtitle file here

Translation Completed!

Drop video file or click to browse

Select Subtitle Track:

No embedded subtitle tracks found

Extraction Complete!

Google Cloud Sync

On-Device AI

API Keys

App Information & Preferences

Cloud Subtitle Archive