Deepgram
Deepgram is a developer speech platform best known for fast, cheap, accurate speech-to-text via its Nova model family, plus Aura text-to-speech and a voice-agent API. Pricing is pay-as-you-go per minute (Nova STT from roughly $0.0077/min, with promotional rates lower) and $200 in free credits to start, making it one of the cheapest production STT options. It's optimized for real-time, high-throughput voice applications and competes directly with AssemblyAI. Like AssemblyAI, it's infrastructure for builders, not a consumer-facing tool.
Stable Audio
Stable Audio is Stability AI's music and sound-effects generator, and the only major player offering open-weight music models trained on fully licensed data. The hosted app (running Stable Audio 2.5) has tiers from free to $89.99/mo, while the Stable Audio 3.0 Small and Medium models released in May 2026 are open weights on Hugging Face, free for commercial use under $1M revenue. That means you can self-host, own your outputs, and generate variable-length tracks up to six minutes. The hosted free tier is thin (10 generations, 30-second crop, non-commercial), but the open-weight option is genuinely unique.
Deepgram edges Stable Audio on aggregate — 86 vs 85.
Among the fastest and cheapest production speech-to-text APIs -- a developer tool, not a consumer app, and a direct AssemblyAI rival. Stable Audio still wins for buyers who prioritise open weights you can self-host and own. Both tools are independently scored — the right pick depends on which dimensions matter most for your workflow.
Side-by-side, every cell sourced.
Pricing pulled from each tool's public site. Scores follow the BigBang Score rubric — pricing transparency, free tier, API support, update frequency, unique factor, documentation, and community.
Use-case picks.
Cut through the spec sheet. Here's what we'd recommend depending on what matters most.
Pick Deepgram if…
You prioritise very fast, low-latency speech-to-text and among the cheapest per-minute stt pricing.
Pick Stable Audio if…
You prioritise open weights you can self-host and own and commercial-friendly community license under $1m revenue.
Editorial pick
Deepgram wins our composite score (86/100). It edges ahead on aggregate — but the right tool depends on which dimensions matter most.
Related head-to-heads in AI audio.
Deepgram vs ElevenLabs — AI audio
BigBang Scores 86/100 vs 88/100. Pricing, capabilities, and editorial verdict inside.
Deepgram vs AssemblyAI — AI audio
BigBang Scores 86/100 vs 88/100. Pricing, capabilities, and editorial verdict inside.
Deepgram vs Cartesia — AI audio
BigBang Scores 86/100 vs 88/100. Pricing, capabilities, and editorial verdict inside.
Deepgram vs Stable Audio - frequently asked.
Direct answers tuned for AI search engines (ChatGPT, Perplexity, Claude) and Google's People Also Ask.
The short answer.
Deepgram wins on aggregate, but Stable Audio pulls ahead on specific axes - the spec sheet above shows where each one earns its keep.