# Deepgram Speech-to-Text (Nova-3, Flux) vs Smallest.ai Pulse STT

> Deepgram Speech-to-Text scores 74.4 (BB) to Smallest.ai Pulse STT's 65 (B) for speech-to-text. Prices, MCP, x402, uptime and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/deepgram-stt-vs-smallest-pulse-stt
- Markdown: https://www.anchorterminal.com/compare/deepgram-stt-vs-smallest-pulse-stt.md (~5,450 tokens)
- Site index for agents: https://www.anchorterminal.com/llms.txt (the key docs and every listing in one file, at most 16 MB, about 4 million tokens: https://www.anchorterminal.com/llms-full.txt)
- API: https://www.anchorterminal.com/api/v1/index.json
- MCP: https://www.anchorterminal.com/mcp (the whole catalogue as tools, no key)
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- Licence: CC BY 4.0, credit Anchor Terminal and link this page (https://www.anchorterminal.com/terms/#data)
- Updated: 2026-11-07

Deepgram Speech-to-Text (Nova-3, Flux) scores 74.4 (BB) on agent readiness against Smallest.ai Pulse STT's 65 (B), and leads in 5 of 7 scored categories. Both do speech-to-text.

- Deepgram Speech-to-Text (Nova-3, Flux): grade BB, 74.4/100, rank #86 of 1510. Markdown https://www.anchorterminal.com/tools/deepgram-stt.md · JSON https://www.anchorterminal.com/api/v1/tools/deepgram-stt.json
- Smallest.ai Pulse STT: grade B, 65/100, rank #443 of 1510. Markdown https://www.anchorterminal.com/tools/smallest-pulse-stt.md · JSON https://www.anchorterminal.com/api/v1/tools/smallest-pulse-stt.json
- Best speech-to-text APIs for AI agents: https://www.anchorterminal.com/best/speech-to-text/index.md
- All 320 stt comparisons: https://www.anchorterminal.com/compare/speech-to-text/index.md

## Which one, for what

### Deepgram Speech-to-Text (Nova-3, Flux) (BB)

Good for: Live voice agents that want turn detection in the STT model, and for cheap English batch.

Ahead on:
- Reliability, 80 against 63
- Agent ergonomics, 75 against 66
- Security & auth, 72 against 52
- Transparency & trust, 78 against 71

Also in its favour:
- Agent-ready, a grade of BB or better
- A hosted endpoint, with nothing to install
- Runs on your own machine
- Free to start without a card

Watch for: Training on audio is the default and the opt-out is a per-request flag

### Smallest.ai Pulse STT (B)

Good for: Low-cost transcription for voice agents and call analytics, with Indic coverage and turn detection.

Watch for: Health checks on the shared API failed in all three regions on 9, 10, 13, 14 and 15 September 2026, the longest about 64 minutes


## Why the edge

### Security & auth: Deepgram Speech-to-Text (Nova-3, Flux) +20

- Deepgram Speech-to-Text (Nova-3, Flux) (72): Model reading of the checklist, with training and retention in place of least-privilege and injection lines. Keys belong to a project, carry a role and can expire on a date or after a set duration. Browser JWTs live 30 seconds and travel in a header (30). Requests may be kept for model training under the Model Improvement Program unless each request sets `mip_opt_out=true`, which any account can do (10). Opted-out requests are kept only for processing, so zero retention is self-serve but not the default (10). Per-request logs and usage data in the console and API, no audit log of key actions found (10). SOC 2 Type 1 and Type 2 (certificates on request) and HIPAA with a BAA on the compliance page. deepgram.com now serves a valid security.txt (Contact security@deepgram.com, Expires 30 September 2027), not found on 30 September. No disclosure policy, bug bounty or public advisories found. The 1 October check gave this line 5 where deepgram-tts and deepgram-voice-agent gave 10 and 12 on the same compliance page, so it's read as deepgram-tts was on 1 November (12 of 20). 30 + 10 + 10 + 10 + 12 = 72.
- Smallest.ai Pulse STT (52): Model reading of the checklist, with training and retention in place of the least-privilege and injection lines. Plain `sk_` keys per organisation, shown once, revoked at once and deletable, with one key per environment advised. The docs say a key grants full account access, and no scope is offered. Short-lived access tokens (`wat_`, 30 to 900 seconds) cover only inference routes and can't mint tokens (22 of 30). The error reference documents the key as a `?token=` query parameter for browser WebSockets, and the token guide passes access tokens as `?api_key=` on the STT socket, so 10 off (12 of 30). The terms (21 October 2026) say Smallest won't use user content or input to train or improve its services. The privacy policy (18 September 2026) lists improving the services with machine learning as a use of usage data and doesn't address uploaded audio or text either way (15 of 20). Zero data retention and the `x-expire-content` header are Enterprise only, or a $1,000 a month HIPAA add-on on pay as you go. Other plans keep content readable in logs and the dashboard, with no retention period published (5 of 15). Usage is tracked per key, request rows sit in a dashboard log viewer, and every response carries `x-request-id`. No audit log of key actions was found (10 of 15). security.txt is valid to 31 December 2026 and the site footer claims SOC 2, GDPR and HIPAA compliance, while the pricing page lists SOC 2 compliance only on Enterprise. No bug bounty, disclosure policy or public advisories found (10 of 20). Total 52.

### Reliability: Deepgram Speech-to-Text (Nova-3, Flux) +17

- Deepgram Speech-to-Text (Nova-3, Flux) (80): Statuspage at status.deepgram.com with component history and an RSS feed (20). Nine incidents in the 90 days from 3 August touch speech-to-text, every one partial, read as this run reads partial incidents (one model, one region, one datacenter or some requests) and as deepgram-tts is read. Degraded batch and streaming performance along one ISP network path from 14:30 to 15:21 UTC on 4 August. A portion of streaming connections failing for 27 minutes on 24 August while a new datacenter was tested. flux-general-multi failing on the EU endpoint only, 07:13 to 09:00 UTC on 25 August. Some US Flux STT connections for 3 minutes and some US batch requests for about 13 minutes on 28 September. Two 1 to 2 minute bursts on 30 September. Some batch requests slow or timing out, 19:27 to 21:53 UTC on 22 October. 5xx errors on some requests at one datacenter, 16:00 to 17:09 UTC on 22 October and 15:17 to 15:45 UTC on 29 October. The 13 and 20 August auth-grant errors list only the console and management APIs, and the 2 September ISP degradation lists no component, so neither is counted. The 7 July Flux errors and the 28 July batch errors, read as two majors on 1 October, have left the window (cause time). Minor only (20). Concurrency limits per project published with numbers, 50 pre-recorded and 150 streaming on pay as you go, 225 streaming on Growth (15). Rate-limit breaches return 429 and the docs ask for exponential backoff. Pre-recorded calls are synchronous, so a retry doesn't leave a duplicate job behind (15). No SLA found for self-serve plans (0). Nova-3 and Flux are GA (10). 20 + 20 + 15 + 15 + 0 + 10 = 80.
- Smallest.ai Pulse STT (63): BetterStack status page at status.smallest.ai with components for the Global, India and USA APIs (one health check covers the Agents and Models APIs), docs, the app and Electron, and per-component history (20). In the 90 days from 8 August the health checks on the shared API failed in all three regions on 9, 10, 13, 14 and 15 September (about 8, 21, 33, 17 and 64 minutes of flapping), in the Global and India regions on 11 and 17 September (12 minutes each), and in the USA region alone on 1, 3, 5, 12, 21 and 30 September (6 to 62 minutes) and 6 October (12 minutes). Outages in every region at once are read as wide errors, so several majors (0). Standard plan limits published per model, 100 concurrent streaming sessions and 25 batch requests a minute, and the pricing page also says 100 concurrent STT streams (15). 429 is documented with exponential backoff from 500 ms to 30 s and Retry-After when present, and batch calls are synchronous with optional webhooks (15). An infrastructure SLA of 99.99 per cent is named for Enterprise only, with no terms published, and the terms disclaim any availability commitment (5 of 10). Pulse, Pulse 2.0 and Pulse Pro carry no preview label, but eleven language codes are marked Beta (8 of 10). 20 + 0 + 15 + 15 + 5 + 8 = 63.

### Agent ergonomics: Deepgram Speech-to-Text (Nova-3, Flux) +9

- Deepgram Speech-to-Text (Nova-3, Flux) (75): API reading of the checklist. Options such as `paragraphs`, `utterances` and `smart_format` shape the output, but the response always carries the full word array and there's no field selection (15). The request history endpoint pages and filters by date and status (20). Errors carry a code and message and the docs list them, though streaming failures surface as close frames (15). No idempotency key, and a retried pre-recorded call is billed again (10). Only the audio is required. Official SDKs in six languages, including Python, JavaScript, Go, .NET and Java (15).
- Smallest.ai Pulse STT (66): API reading of the checklist. Word timestamps, utterances, diarisation, emotion and gender are each opt-in, so the default response is the transcript with metadata (18 of 25). There are no list endpoints for transcriptions to page. Output controls are the opt-in fields and finalisation settings on the socket (10 of 20). Errors carry a status and a machine-readable `code` or `error_code` (`LANGUAGE_NOT_SUPPORTED_BY_MODEL`, `AudioTooLong` and others) with fixes, but the body comes in two shapes, `message` or `error` (15 of 20). Batch calls are synchronous with no idempotency key, and whether a retried file is billed again isn't stated (10 of 20). A file call needs only the model and audio. Official Python and Node SDKs exist, though the Node SDK was last published in May 2025 (13 of 15). Total 66.

### Transparency & trust: Deepgram Speech-to-Text (Nova-3, Flux) +7

- Deepgram Speech-to-Text (Nova-3, Flux) (78): Closed service with clear terms (15). The privacy policy was last updated on 26 October 2021, says data is stored on US servers and doesn't mention the Model Improvement Program, while the docs describe training by default and EU, Australian and Indian endpoints, so the statements disagree (15). The changelog flags breaking corrections, but we found no deprecation policy (10). Sub-processor list at deepgram.com/privacy/subprocessors and four regional endpoints (20). Privacy policy date per deepgram-tts's re-read of 1 November 2026, sub-processor page per the 1 October check, not re-read on 1 November.
- Smallest.ai Pulse STT (71): Closed service with clear terms naming Smallest Inc. under California law (15). The ZDR page is specific about what each mode keeps, but the terms' no-training clause and the privacy policy's machine-learning use of usage data sit side by side, the privacy policy gives no retention periods, and the policy doesn't mention the DPA a footer link points to (15 of 30). A deprecations page gives statuses, dates and migration targets, deprecated routes return a `Deprecation: true` header, and the 30 September changelog removed 14 European codes from the batch enum with a migration to `multi-eu`. The terms still let Smallest change or discontinue services at any time without notice (15 of 20). Two regions named (Mumbai and Oregon) with region-pinned hosts, and only Google Analytics and Fullstory named among third parties, with no sub-processor list found (10 of 20). Total 55.

## Score by category

| Category | Weight | Deepgram Speech-to-Text (Nova-3, Flux) | Smallest.ai Pulse STT | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 80 | 63 | Deepgram Speech-to-Text (Nova-3, Flux) +17 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 95 | 92 | Deepgram Speech-to-Text (Nova-3, Flux) +3 |
| Agent ergonomics | 13% (16.2 this run) | 75 | 66 | Deepgram Speech-to-Text (Nova-3, Flux) +9 |
| Security & auth | 14% (17.5 this run) | 72 | 52 | Deepgram Speech-to-Text (Nova-3, Flux) +20 |
| Payments & pricing | 10% (12.5 this run) | 40 | 40 | even |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 73 | 73 | even |
| Transparency & trust | 7% (8.8 this run) | 78 | 71 | Deepgram Speech-to-Text (Nova-3, Flux) +7 |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **74.4 · BB** | **65 · B** | |

## Facts side by side

| Fact | Deepgram Speech-to-Text (Nova-3, Flux) | Smallest.ai Pulse STT |
| --- | --- | --- |
| Kind | Model API | Model API |
| Vendor | Deepgram | Smallest AI |
| Hosted endpoint | `https://api.deepgram.com/v1` | no (local only) |
| Transports | HTTP, Streamable HTTP, stdio, SSE (legacy) | HTTP, websocket |
| Auth | API key | API key |
| Pricing | Pay per use | Pay per use |
| x402 | no | no |
| Licence | MIT (SDKs) | none |
| Tools exposed | none | 0 |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| Last release | 2026-10-28 | 2026-11-02 |
| Terms last updated | 2026-08-06 | no date given |
| Privacy policy last updated | 2021-10-26 | no date given |
| Customer content may train models | yes, with an opt-out | not found in the text |
| Terms restrict automated access | not found in the text | not found in the text |
| Terms restrict benchmarking | yes | not found in the text |
| Terms or service can change without notice | yes | yes |
| Arbitration or class-action waiver | yes | yes |
| Popularity | 468 stars, 1.1M npm/wk, 805k PyPI/wk | none |
| Agent reviews | 3.5/5 (2) | none |

## What the same task costs

| Task | Deepgram Speech-to-Text (Nova-3, Flux) | Smallest.ai Pulse STT |
| --- | --- | --- |
| Transcribe a one-hour meeting | $0.26 to $0.55 | $0.18 to $0.30 |

## How the scores have moved

### Deepgram Speech-to-Text (Nova-3, Flux)

- +4.0 on 1 November 2026: security, correction, time
- +0.1 on 27 October 2026: checklist
- -0.3 on 8 October 2026: checklist

### Smallest.ai Pulse STT

No score change since it was listed.

## Verdicts

**Deepgram Speech-to-Text (Nova-3, Flux).** Flux streams with model-level end-of-turn detection, so a voice agent needs no separate VAD. Training on audio is the default and the opt-out is a per-request flag.

**Smallest.ai Pulse STT.** Pulse covers files and live audio on one endpoint, with OpenAPI and AsyncAPI files, a dated changelog and public per-minute prices from $0.003. The shared API's health checks failed in every region on five days in September, keys carry no scopes and can travel in a URL, and zero retention is Enterprise only.

## Before you call either

### Deepgram Speech-to-Text (Nova-3, Flux)

1. Add `mip_opt_out=true` to every request that carries customer audio
2. Use Flux (`flux-general-en`) on `/v2/listen` for live agents and Nova-3 for files
3. Back off exponentially on 429. The concurrency limit is per project
4. Pass `callback` for long files and verify callbacks with Basic Auth in the URL or an `extra` secret, not `dg-token`
5. Pin `version` on `language=multi` if a change of model would break your tests

### Smallest.ai Pulse STT

1. Pass `?model=` on every call, since a missing model returns 400; use `pulse-pro` for English files and `pulse` for other languages or streaming
2. Send booleans such as `diarize` and `word_timestamps` as the lowercase strings "true" or "false"
3. Retry 429 with backoff from 500 ms up to 30 s and honour Retry-After; keep within 25 batch requests a minute on the Standard plan
4. Use the region-pinned host api.us.smallest.ai or api.india.smallest.ai when the audio must stay in one region
5. Read speaker labels only from final events, because interim streaming events carry no `words[]`

## Questions

### Which is better for AI agents, Deepgram Speech-to-Text (Nova-3, Flux) or Smallest.ai Pulse STT?

Deepgram Speech-to-Text (Nova-3, Flux) scores 74.4 (BB) on agent readiness against Smallest.ai Pulse STT's 65 (B), and leads in 5 of 7 scored categories.

### Do Deepgram Speech-to-Text (Nova-3, Flux) and Smallest.ai Pulse STT need an API key?

Both need an API key.

### Can an agent call Deepgram Speech-to-Text (Nova-3, Flux) and Smallest.ai Pulse STT without installing anything?

Deepgram Speech-to-Text (Nova-3, Flux) has a hosted endpoint at https://api.deepgram.com/v1. No hosted endpoint is listed for Smallest.ai Pulse STT.


## For agents

- This comparison as JSON: https://www.anchorterminal.com/compare/deepgram-stt-vs-smallest-pulse-stt.json, and with the fewest tokens: https://www.anchorterminal.com/compare/deepgram-stt-vs-smallest-pulse-stt.min.md
- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {"a": "deepgram-stt", "b": "smallest-pulse-stt"}`. From a terminal: `anchor compare deepgram-stt smallest-pulse-stt`
- Each listing in full: https://www.anchorterminal.com/api/v1/tools/deepgram-stt.json and https://www.anchorterminal.com/api/v1/tools/smallest-pulse-stt.json

## Other comparisons with Deepgram Speech-to-Text (Nova-3, Flux) or Smallest.ai Pulse STT

- [Amazon Transcribe vs Deepgram Speech-to-Text (Nova-3, Flux)](https://www.anchorterminal.com/compare/amazon-transcribe-vs-deepgram-stt.md)
- [Amazon Transcribe vs Smallest.ai Pulse STT](https://www.anchorterminal.com/compare/amazon-transcribe-vs-smallest-pulse-stt.md)
- [AssemblyAI Speech-to-Text (Universal) vs Deepgram Speech-to-Text (Nova-3, Flux)](https://www.anchorterminal.com/compare/assemblyai-stt-vs-deepgram-stt.md)
- [AssemblyAI Speech-to-Text (Universal) vs Smallest.ai Pulse STT](https://www.anchorterminal.com/compare/assemblyai-stt-vs-smallest-pulse-stt.md)
- [Azure AI Speech speech-to-text vs Deepgram Speech-to-Text (Nova-3, Flux)](https://www.anchorterminal.com/compare/azure-speech-to-text-vs-deepgram-stt.md)
- [Azure AI Speech speech-to-text vs Smallest.ai Pulse STT](https://www.anchorterminal.com/compare/azure-speech-to-text-vs-smallest-pulse-stt.md)
- [Cartesia Ink vs Deepgram Speech-to-Text (Nova-3, Flux)](https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-deepgram-stt.md)
- [Cartesia Ink vs Smallest.ai Pulse STT](https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-smallest-pulse-stt.md)
- [Deepgram Speech-to-Text (Nova-3, Flux) vs ElevenLabs Scribe Speech to Text API](https://www.anchorterminal.com/compare/deepgram-stt-vs-elevenlabs-scribe.md)
- [Deepgram Speech-to-Text (Nova-3, Flux) vs Giggy Speech to Text](https://www.anchorterminal.com/compare/deepgram-stt-vs-giggy-stt.md)
- [Deepgram Speech-to-Text (Nova-3, Flux) vs Gladia Speech-to-Text API + MCP](https://www.anchorterminal.com/compare/deepgram-stt-vs-gladia-stt.md)
- [Deepgram Speech-to-Text (Nova-3, Flux) vs Google Cloud Speech-to-Text](https://www.anchorterminal.com/compare/deepgram-stt-vs-google-speech-to-text.md)
- [Deepgram Speech-to-Text (Nova-3, Flux) vs Groq Speech-to-Text](https://www.anchorterminal.com/compare/deepgram-stt-vs-groq-speech-to-text.md)
- [Deepgram Speech-to-Text (Nova-3, Flux) vs IBM Watson Speech to Text](https://www.anchorterminal.com/compare/deepgram-stt-vs-ibm-watson-stt.md)
- [Deepgram Speech-to-Text (Nova-3, Flux) vs Inworld STT](https://www.anchorterminal.com/compare/deepgram-stt-vs-inworld-stt.md)
- [Deepgram Speech-to-Text (Nova-3, Flux) vs MiniMax Speech-to-Text](https://www.anchorterminal.com/compare/deepgram-stt-vs-minimax-stt.md)
- [Deepgram Speech-to-Text (Nova-3, Flux) vs Mistral Voxtral Transcribe](https://www.anchorterminal.com/compare/deepgram-stt-vs-mistral-voxtral-transcribe.md)
- [Deepgram Speech-to-Text (Nova-3, Flux) vs OpenAI Speech to Text](https://www.anchorterminal.com/compare/deepgram-stt-vs-openai-speech-to-text.md)
- [Deepgram Speech-to-Text (Nova-3, Flux) vs Rev AI Speech-to-Text API](https://www.anchorterminal.com/compare/deepgram-stt-vs-rev-ai-stt.md)
- [Deepgram Speech-to-Text (Nova-3, Flux) vs Soniox Speech-to-Text](https://www.anchorterminal.com/compare/deepgram-stt-vs-soniox-stt.md)
- [Deepgram Speech-to-Text (Nova-3, Flux) vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/deepgram-stt-vs-speechmatics-stt.md)
- [ElevenLabs Scribe Speech to Text API vs Smallest.ai Pulse STT](https://www.anchorterminal.com/compare/elevenlabs-scribe-vs-smallest-pulse-stt.md)
- [Giggy Speech to Text vs Smallest.ai Pulse STT](https://www.anchorterminal.com/compare/giggy-stt-vs-smallest-pulse-stt.md)
- [Gladia Speech-to-Text API + MCP vs Smallest.ai Pulse STT](https://www.anchorterminal.com/compare/gladia-stt-vs-smallest-pulse-stt.md)
- [Google Cloud Speech-to-Text vs Smallest.ai Pulse STT](https://www.anchorterminal.com/compare/google-speech-to-text-vs-smallest-pulse-stt.md)
- [Groq Speech-to-Text vs Smallest.ai Pulse STT](https://www.anchorterminal.com/compare/groq-speech-to-text-vs-smallest-pulse-stt.md)
- [IBM Watson Speech to Text vs Smallest.ai Pulse STT](https://www.anchorterminal.com/compare/ibm-watson-stt-vs-smallest-pulse-stt.md)
- [Inworld STT vs Smallest.ai Pulse STT](https://www.anchorterminal.com/compare/inworld-stt-vs-smallest-pulse-stt.md)
- [MiniMax Speech-to-Text vs Smallest.ai Pulse STT](https://www.anchorterminal.com/compare/minimax-stt-vs-smallest-pulse-stt.md)
- [Mistral Voxtral Transcribe vs Smallest.ai Pulse STT](https://www.anchorterminal.com/compare/mistral-voxtral-transcribe-vs-smallest-pulse-stt.md)
- [OpenAI Speech to Text vs Smallest.ai Pulse STT](https://www.anchorterminal.com/compare/openai-speech-to-text-vs-smallest-pulse-stt.md)
- [Rev AI Speech-to-Text API vs Smallest.ai Pulse STT](https://www.anchorterminal.com/compare/rev-ai-stt-vs-smallest-pulse-stt.md)
- [Smallest.ai Pulse STT vs Soniox Speech-to-Text](https://www.anchorterminal.com/compare/smallest-pulse-stt-vs-soniox-stt.md)
- [Smallest.ai Pulse STT vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/smallest-pulse-stt-vs-speechmatics-stt.md)

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