Accurately convert
Japanese MP4 files to text
Sonix automatically transcribes your Japanese MP4 files to text in minutes. Access industry-leading artificial intelligence and the days of manually transcribing your Japanese MP4 files are long gone. Japanese speech to text: Sonix has been independently reviewed the most accurate Japanese automated transcription, translation, and subtitling platform.
Free to start — no credit card required.
Thousands of Sonix customers convert their Japanese MP4 files to text











Use Sonix to quickly convert
Japanese MP4 files to text
- 1Log into your Sonix account~30 sec
If you don't have one, you can sign up for Sonix's free account — Your free trial includes 30 minutes of transcription and translation.
- 2Upload your Japanese MP4 file~1 min
Click “Upload” and locate the Japanese MP4 file on your computer.
- 3Choose language: Japanese~10 sec
Select Japanese as the language spoken, then click “Transcribe”.
- 4Sonix transcribes your MP4 file~5 min
Sonix transcribes your Japanese MP4 file and converts it to Japanese text.
- 5Polish your Japanese transcript~2 min
Edit your Japanese transcript directly in the browser to correct any misheard words.
- 6Export Japanese text~10 sec
Export the Japanese text to MS Word, PDF, subtitles, or plain text.
Understanding Japanese MP4 files
Standard Japanese (hyojungo), based on Tokyo speech, dominates broadcasting and education and is the variety speech recognition models are primarily trained on. Kansai dialect (Osaka and Kyoto) is the most prominent regional variant, with different pitch accent and vocabulary, while Tohoku and Kyushu dialects diverge further from the standard; the traditional Ryukyuan languages of Okinawa differ so much that linguists classify them as separate languages rather than Japanese dialects.
MP4 technical specifications
- Codec
- Various (commonly H.264/AVC or H.265/HEVC video with AAC audio)
- Container
- MPEG-4 Part 14
- Typical bitrate
- Varies widely by resolution and codec; AAC audio tracks are commonly 96–320 kbps
- Sample rate
- Audio track typically 44.1 or 48 kHz
- Compression
- Container (varies)
Japanese at a glance
- Speakers
- ~125 million speakers worldwide
- Writing system
- Mixed script: kanji (Chinese characters) combined with the hiragana and katakana syllabaries, written without spaces between words
- Say hello
- こんにちは (Kon'nichiwa)!
Frequently asked questions
How to improve the accuracy of your Japanese transcripts?
Start by improving the quality of the Japanese MP4 file that you upload to Sonix. Please use high quality recording equipment, recording in a quiet environment, and ensure that your speakers are speaking clearly to ensure that your transcript is as accurate as possible.
Any advice for the Japanese MP4 file that I upload?
Yes, please do not over-compress or over-filter the audio track of your Japanese MP4 file. By uploading a high quality version of your audio, we can give you the best level of accuracy.
Aside from MP4, do you support other types of audio/video files?
Yes, we do! You can convert the following file types in Japanese with Sonix:
Do I need to extract the audio from an MP4 before transcribing it?
No. Because MP4 is a container that holds both video and audio streams, the audio track can be read directly from the file, so you can upload the video as is.
Why does my MP4 file play video but no sound?
The file may contain a video stream with no audio track, or its audio may use a codec your player does not support. Checking the file's stream details in a tool like VLC or re-exporting it with an AAC audio track usually resolves the issue.
Can Sonix transcribe Japanese audio and video to text?
Yes. Upload your audio or video file, select Japanese as the spoken language, and Sonix returns a transcript in standard Japanese script (kanji, hiragana, and katakana) that you can edit in the browser and export.
Does Japanese transcription handle Kansai dialect and regional accents?
Sonix's Japanese model is built around standard (Tokyo) Japanese and generally handles regional accents, but strongly dialectal vocabulary such as Kansai-ben expressions may need corrections in the built-in editor.
Can Sonix create Japanese subtitles?
Yes. After transcribing, you can split the Japanese transcript into subtitle lines and export SRT or VTT files for video captioning.
Trusted by professionals worldwide
Found you through Google. Super easy to use. Transcribed 98% correctly even though it was not a great audio file.
We love transcribing with Sonix. Your interface for subtitle editing is excellent.
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