Soniox vs Deepgram
for English speech-to-text

Higher accuracy in real-world English, real-time features, and in-stream translation that Deepgram can't match.

Developers choose Soniox for accuracy in English speech

English is spoken by 1.5 billion people worldwide — across United States, United Kingdom, Canada, Australia, New Zealand, Ireland, South Africa, and beyond. Soniox delivers production-ready transcription and translation for English, handling regional accents, code-switching, and real-world audio conditions. Deepgram lists English as supported, but benchmark results show far higher error rates compared to Soniox.

Developers often like Deepgram for getting started quickly but often have to sacrifice accuracy, streaming speed, and key features. In real-world English audio, which can include accents, rapid speech, and overlapping speakers, errors increase, streaming lags, and translation isn't included. Soniox offers one API that transcribes and translates English (and 60+ others) with higher accuracy and smoother real-time performance, so your app instantly works worldwide.

Trusted accuracy

Soniox outperforms Deepgram on real-world English speech, so there's less to fix later. Soniox hits 6.5% WER in English vs 9.9% for Deepgram.

Faster streaming in English

Apps feel smooth and human with token-level updates, refinements, and full transcript control in English.

English translation built in

One API delivers transcription and two-way translation across 60+ languages, including English. Your app works for 8 billion people worldwide with no extra services required.

Helping startups and enterprises ship real world voice apps

See the difference for yourself

Don't just take our word for it. Run the same English audio through Soniox and Deepgram in real-time and compare live results, side by side.

This demo isn't pre-recorded. It makes real API calls to Deepgram and Soniox in real-time, with each service tuned for its best performance. The framework is open source, so you can inspect or run it yourself.

SONIOX VS DEEPGRAM AT A GLANCE

The benchmarks back it up

In a 2025 study across 60 languages and real-world YouTube audio, Soniox reached 6.5% WER in English vs 9.9% for Deepgram.

View the full benchmark report

Feature	Sonioxstt-rt-v3	Deepgramnova-3
open_in_newSingle Multilingual Model	check	check
open_in_newLanguage Hints	check	close
open_in_newLanguage Identification	check	close
open_in_newSpeaker Diarization	check	check
open_in_newCustomization	check	check
open_in_newTimestamps	check	check
open_in_newConfidence Scores	check	check
open_in_newTranslation One Way	check	close
open_in_newTranslation Two Way	check	close
open_in_newEndpoint Detection	check	warning^*
open_in_newManual Finalization	check	check

Pay 2-3x less than Deepgram

With Soniox, transcription, translation, diarization, timestamps, and confidence are all included in one price. Deepgram charges more per tier and doesn't bundle translation at all.

Effective hourly cost

(typical speech)

Soniox

~$0.10/hour (async)
~$0.12/hour (streaming)

Deepgram

~$0.20–0.40/hour depending on model tier (Nova-2, Nova-3, Enhanced)

100 hours

1,000 hours

10,000 hours

Soniox (async)

~$10

~$100

~$1,000

Soniox (streaming)

~$12

~$120

~$1,200

Deepgram (typical)

~$20-40

~$200-400

~$2,000-4,000

Takeaway

For English, you'll typically pay 2–3x less than Deepgram, while getting higher accuracy, smoother streaming, and built-in translation out of the box.

Soniox bills per token, which works out to the effective hourly rates above for typical conversational speech.
Deepgram pricing varies by tier: lower-cost "Nova" models are less accurate, while higher-cost "Enhanced" adds expense. Translation requires a separate service.
All comparisons use publicly listed rates as of 2025.

Why teams choose Soniox over Deepgram for English

Engineered for real-world accuracy in English.

Soniox delivers production-grade accuracy in English and 60+ languages. It understands fast, informal, accented speech in English, and handles mixed-language phrases, spoken codes, and alphanumerics with precision that others miss.

"It just gets the words right — any language, any accent, any context. That’s what accuracy is supposed to look like."

Tony Wang,
Cofounder & Chief Revenue Officer at Agora

Deepgram’s accuracy drops outside of English, and it struggles with English accents, code-switching, and real-world inputs like spelled-out names or numbers.

Unmatched speed and precision in English.

Soniox streams every English word in real time – accurate from the first sound, fluent to the last. Captions stay in sync, assistants respond instantly, and nothing gets lost mid-sentence.

"It’s so fast, captions appear before people even finish talking. Zero lag. No buffering. Nothing."

Dag-Inge Aas,
Head of AI at Tana

Deepgram streams by the sentence, not the word, which causes lag and loss of nuance in live applications.

Understand the rhythm of real English speech.

Soniox knows when someone’s speaking, when they’ve stopped, and who’s talking, with built-in speaker separation, sentence boundary detection, and turn-taking awareness.

"Soniox knows who’s speaking and when each thought ends. The real-time transcripts read like true dialogue, not data dumps."

Adam Strom,
Co-Founder & President at Mobius MD

Deepgram lacks true conversational intelligence, and doesn’t support diarization in multilingual settings.

One API. Everything built in.

English transcription, any-to-any translation, speaker separation, mixed-language support – all from a single model, endpoint, and call. Production-ready from day one.

Deepgram splits features across models, with no multilingual or translation support in a single stream.

Instant domain intelligence.

Soniox catches product names, acronyms, technical terms, and can be guided with your terminology — so output fits your users, product, and industry.

"Soniox's ability to accurately transcribe complex medical terminology means our physician-customers spend significantly less time editing. This allows them to finalize their notes faster and focus on what matters most: patient care."

Max Malyk,
Vice President at DeliverHealth

Deepgram lacks domain intelligence, and doesn’t support vocab customization or translation control.

Fluent at any speed

Watch Soniox keep up with fast speech in any language

Chinese to English in real-time

Very fast speaking Spanish translated in real-time in English

Real time translation from Japanese to English

Real-Time Translation Demo | From German to English

French speech to Text | Leslie Talks About Monster eating a Cake

Russian to English

Speaking Super Fast in Italian – Soniox still translated every word into English

Korean to English in real-time

Real-Time from Slovenian to English

Valeria Juri Reads Ukrainian Poem “Мовчати” | Live English Translation

Frequently asked questions about Soniox vs Deepgram

1.Is Soniox cheaper than Deepgram?arrow_downward

Yes. Soniox costs ~$0.10–0.12/hr, while Deepgram typically costs ~$0.20–0.40/hr depending on model tier. That's 2–3x less expensive.

2.Does Deepgram support English translation?arrow_downward

No. Deepgram only provides transcription. Soniox includes two-way, in-stream translation across 60+ languages in the same API call.

3.How does Soniox streaming compare to Deepgram?arrow_downward

Soniox streams token by token in milliseconds, with refinements, manual finalization, and endpoint detection. Deepgram streams by the sentence, creating lag and jumpy transcripts.

4.Does Deepgram support diarization and timestamps?arrow_downward

Yes, but Soniox provides them faster and in real-time.

5.Can Soniox handle multiple languages in one stream?arrow_downward

Yes. Soniox detects language shifts mid-conversation. Deepgram requires a single language per request.

Soniox surpasses Deepgram in any language

Get the most accurate, real-time speech-to-text transcription and translation in 60+ languages

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Soniox vs Deepgram for English speech-to-text