Get the AppBuild with API

English to Vietnamese speech translation API

Stream English (English) speech and get Vietnamese (Tiếng Việt) back in real time. One WebSocket, ISO codes en to vi, and ultra-low latency for voice agents and live apps.

Trusted by

Production-ready English to Vietnamese translation API

Real English speech includes accents, regional dialects, code switching, and domain-specific vocabulary. Soniox recognizes it in a single model and streams Vietnamese while the speaker is still talking.

English (Indo-European > Germanic > West Germanic) and Vietnamese (Austroasiatic > Vietic) come from different language families, so word order and morphology differ. Soniox reorders meaning in-stream instead of word by word.

Soniox preserves formatting in the translated transcript, including names, numbers, addresses, IDs, and domain-specific terms.

A breakthrough in real-time English to Vietnamese translation

check

Translate before the sentence ends

Vietnamese meaning lands as English is spoken, not after the caption catches up.

check

Directional en to vi streaming

Set the source and target codes once. Both arrive in a single labeled token stream.

check

High quality Vietnamese output

Same model across every language, including historically underserved ones.

check

Native-speaker English STT accuracy

Accurate Vietnamese translation starts with accurate English recognition across accents and language switching.

check

Names, numbers, and domain terms

Preserved across the pair, including phone numbers, emails, and IDs.

config.json
{
  "model": "stt-rt-v4",
  "translation": {
    "type": "one_way",
    "source_language": "en",
    "target_language": "vi"
  }
}

English and Vietnamese through a single stream

English to Vietnamese translation is built on top of Soniox Speech-to-Text API. Every spoken word is transcribed, and Vietnamese translation streams mid-sentence in the same labeled token stream.

Turn it on by adding a translation block with source_language: "en" and target_language: "vi". It runs on the same WebSocket and the same model, with no extra round trip.

Live English to Vietnamese: written and spoken

English to Vietnamese speech-to-text

micLive English speecharrow_right_altsubjectVietnamese text

Translate live English into written Vietnamese with the Soniox STT API. Soniox streams the English transcript and the Vietnamese translation as speech happens.

Use it for Vietnamese captions, subtitles, meeting translation, agent assist, and multilingual transcription.

English to Vietnamese speech-to-speech

micLive English speecharrow_right_altvolume_upSpoken Vietnamese

Build full spoken English to Vietnamese translation by combining Soniox STT and Soniox TTS. Soniox recognizes English, translates it, and speaks Vietnamese with low latency.

Use it for live interpreters, bilingual voice agents, travel assistants, and customer support.

Live English to Vietnamese translation in action

Stream English to Vietnamese one-way to push all speech into Vietnamese, or two-way to keep a bilingual conversation flowing between the two languages.

voice_selection
English speaker says: “Oh, FYI, the client moved the demo to 9:30, so we’re not totally sprinting.”
translate
Translated into Vietnamese in real time.

One-way translation

Translate live English into Vietnamese. Everyone in the conversation sees the same translated stream.

Ideal for live captions, multilingual meetings, broadcasts, lectures, and customer calls.

voice_selection
English speaker talks in English.
hearing
Vietnamese speaker hears Vietnamese.
voice_selection
Vietnamese speaker replies in Vietnamese.
hearing
English speaker hears English.

Two-way translation

Translate between English and Vietnamese for live bilingual conversation. Each side speaks naturally and hears the other in their own language.

Soniox supports real-time two-way translation between any two of 60+ supported languages.

Accurate on both ends of the pair

Soniox transcribes English at 6.5% word error rate and Vietnamese at 5.4% word error rate. Accurate recognition on both sides is what makes the translation reliable.

speech_to_text

Speech-to-Text

Native-speaker accuracy across 60+ languages, with support for multilingual speech, alphanumerics, speaker diarization, context.

translate

Translation

Real-time streaming translation across 3,600 language pairs, built for high quality and low delay across all supported languages.

text_to_speech

Text-to-speech

High-fidelity speech generation in 60+ languages, built for names, alphanumerics, language switching, and ultra-low-latency streaming.

Together, they create a complete real-time low-latency speech AI platform.

quiz
About English and Vietnamese

English has roughly 1,500,000,000 speakers across United States, United Kingdom, Canada, and Australia. Vietnamese has roughly 95,000,000 speakers across Vietnam.

English is the most widely spoken language in the world when including both native and non-native speakers.

Vietnamese was historically written in Chinese characters (Chữ Hán) and a modified form called Chữ Nôm.

Soniox makes English to Vietnamese usable in real-time translation across every supported pair.

Translate English to any language

From English to Vietnamese, or English to any of 60+ supported languages. All real-time.

AfrikaansAlbanianArabicAzerbaijaniBasqueBelarusianBengaliBosnianBulgarianCatalanChineseCroatianCzechDanishDutchEstonianFinnishFrenchGalicianGermanGreekGujaratiHebrewHindiHungarianIndonesianItalianJapaneseKannadaKazakhKoreanLatvianLithuanianMacedonianMalayMalayalamMarathiNorwegianPersianPolishPortuguesePunjabiRomanianRussianSerbianSlovakSlovenianSpanishSwahiliSwedishTagalogTamilTeluguThaiTurkishUkrainianUrduVietnameseWelsh

Related translation pages

swap_horizTranslate Vietnamese to Englisharrow_right_alttranslateEnglish speech translationarrow_right_alttranslateVietnamese speech translationarrow_right_altarrow_right_altEnglish to Dutcharrow_right_altarrow_right_altEnglish to Germanarrow_right_altarrow_right_altEnglish to Afrikaansarrow_right_alt

Frequently asked questions

How do I translate English to Vietnamese with the API?arrow_downward
Add a translation block to your real-time request with source_language "en" and target_language "vi". Soniox transcribes English and streams the Vietnamese translation over the same WebSocket.
Is English to Vietnamese translation real-time?arrow_downward
Yes. Soniox streams Vietnamese while English is still being spoken, so meaning arrives mid-sentence instead of after the sentence ends.
What about translating Vietnamese to English?arrow_downward
That direction is supported too. See the Vietnamese to English page, or use two-way translation to run both directions in one session.
Does Soniox handle English dialects and accents?arrow_downward
Yes. Soniox handles English dialects like American English, British English, and Australian English in a single model, so Vietnamese translation stays accurate across regions.
Which other providers support English to Vietnamese?arrow_downward
Based on their public docs, OpenAI, Azure, and Speechmatics list both English and Vietnamese for real-time translation. Soniox is the only one that also supports two-way live translation across 60+ languages.
How fast is English to Vietnamese translation?arrow_downward
Soniox streams Vietnamese as English is being spoken, with ultra-low latency. Translation arrives before the sentence ends.

Ready to get started?

Create an account instantly, or contact us to design a custom package for your business.

Build with API arrow_right_alt

Documentation

Get up and running in minutes and spend your time building the product, not wrestling with the API.

Explore docs

See what you’ll pay

Pay only for what you use with our flexible pricing. Built to scale with you.

Pricing details