How to Choose the Right STT Provider for OpenTypeless

OpenTypeless supports 6 speech-to-text providers, each with different strengths in accuracy, speed, language coverage, and pricing. Choosing the right one can dramatically improve your voice input experience. This guide provides a detailed comparison to help you pick the best provider for your specific use case.

How Speech-to-Text Works

Before diving into providers, it helps to understand what happens when you speak into OpenTypeless. Your microphone captures audio, which is compressed and sent to the STT provider's API. The provider runs the audio through a neural network trained on thousands of hours of speech data, producing a text transcription. Different providers use different model architectures, training data, and optimization strategies — which is why accuracy and speed vary significantly between them.

The key metrics to consider are: word error rate (WER) — the percentage of words transcribed incorrectly; latency — how quickly you get results back; language support — which languages and dialects are supported; and pricing — cost per minute of audio processed. There's no single 'best' provider — the right choice depends on your primary language, latency requirements, and budget.

Deepgram Nova-3

Deepgram Nova-3 is the best overall choice for English-speaking users. It's Deepgram's latest model, trained specifically for conversational speech with excellent handling of technical vocabulary, proper nouns, and natural speech patterns. Nova-3 achieves industry-leading word error rates on English benchmarks, consistently outperforming other providers in head-to-head comparisons.

What sets Deepgram apart is its smart formatting. The API automatically adds punctuation, capitalizes proper nouns, and formats numbers correctly. This means less work for the LLM polishing step — the raw transcription is already quite clean. Deepgram also supports real-time streaming, so you can see words appear as you speak rather than waiting for the entire recording to process.

• Best-in-class English accuracy with smart formatting
• Real-time streaming support for instant feedback
• $200 free credit on signup — enough for months of personal use
• 36+ languages supported with varying accuracy levels

OpenAI Whisper

OpenAI's Whisper is the most versatile option, supporting over 50 languages with consistent quality across all of them. Whisper was trained on 680,000 hours of multilingual audio data, giving it remarkable robustness to accents, background noise, and domain-specific vocabulary. If you regularly switch between languages or work in a non-English language, Whisper is a strong default choice.

The trade-off is speed. Whisper processes audio in batch mode rather than streaming, which means you need to wait for the entire recording to finish before getting results. For short voice inputs (under 30 seconds), this delay is barely noticeable. For longer recordings, it can feel sluggish compared to streaming providers like Deepgram.

• 50+ languages with consistent quality across all of them
• Excellent noise robustness — works well in noisy environments
• Strong technical vocabulary handling across domains
• Batch processing only — no real-time streaming

Groq Whisper

Groq Whisper is the speed champion. Groq runs the same Whisper model on custom LPU (Language Processing Unit) hardware, delivering transcription results 5-10x faster than OpenAI's hosted version. In our testing, a 10-second audio clip returns results in under 200 milliseconds — essentially instant. You get the same accuracy as OpenAI Whisper but with dramatically lower latency.

If latency is your top priority — for example, if you're using voice input in real-time conversations or rapid-fire coding sessions — Groq Whisper is the clear winner. The speed difference is immediately noticeable and makes voice input feel much more responsive.

• 5-10x faster than standard Whisper — near-instant results
• Same accuracy as OpenAI Whisper (same model, faster hardware)
• 50+ language support inherited from Whisper
• Free tier available with generous rate limits

GLM-ASR

GLM-ASR by Zhipu AI is the best choice for Chinese speakers. It's specifically optimized for Mandarin and Chinese dialects, with training data focused on Chinese conversational patterns, technical terminology, and code-switching between Chinese and English. If Chinese is your primary language, GLM-ASR will significantly outperform general-purpose models like Whisper on Chinese content.

GLM-ASR handles the unique challenges of Chinese speech recognition well: tone disambiguation, homophone resolution, and proper segmentation of Chinese characters. It also correctly handles mixed Chinese-English speech, which is common in technical discussions where English terms are used within Chinese sentences.

• Best-in-class Mandarin accuracy with dialect support
• Excellent Chinese-English code-switching handling
• Competitive pricing through Zhipu AI's API

AssemblyAI

AssemblyAI differentiates itself with audio intelligence features beyond basic transcription. Their Universal-2 model offers strong accuracy across 30+ languages, with additional capabilities like speaker diarization (identifying who said what), sentiment analysis, and topic detection. For OpenTypeless's voice input use case, the core transcription quality is solid and reliable.

AssemblyAI is a good choice if you value consistent, reliable transcription and might want to explore advanced audio features in the future. Their API is well-documented and their free tier is generous enough for personal use.

SiliconFlow

SiliconFlow offers budget-friendly STT with competitive quality. They host open-source models on optimized infrastructure, passing the cost savings to users. If you're processing large volumes of audio or are cost-sensitive, SiliconFlow provides good value. The accuracy is slightly below the top-tier providers but perfectly adequate for voice input with AI polishing — the LLM step catches most transcription imperfections anyway.

How to Switch Providers

Switching providers in OpenTypeless takes about 10 seconds. Open Settings, go to the STT tab, select your new provider from the dropdown, and enter your API key. OpenTypeless validates the key immediately and you're ready to go. Your previous provider's API key is saved, so you can switch back anytime without re-entering credentials.

Settings → STT Provider → Select provider → Enter API key → Done

Our Recommendation

For most English users, start with Deepgram Nova-3 — the accuracy and smart formatting are hard to beat, and the $200 free credit removes any cost barrier. If you need the fastest possible response, switch to Groq Whisper. For Chinese users, GLM-ASR is the clear choice. For multilingual users who switch between languages frequently, OpenAI Whisper's broad language support makes it the safest default.