Head to head · Speech-to-text · October 2026 research run

Azure AI Speech speech-to-text vs MiniMax Speech-to-Text

Azure AI Speech speech-to-text scores 75.1 (BB) on agent readiness against MiniMax Speech-to-Text's 48.4 (D), and leads in 5 of 7 scored categories. Both do speech-to-text.

Best speech-to-text APIs for AI agents · All 320 stt comparisons

Which one, for what

Azure AI Speech speech-to-text BB

Best for Teams on Azure who need several modes (real time, synchronous files, cheap batch, custom models) under one resource, or strict default data handling.

Ahead on

  • Reliability, 90 against 47
  • Agent ergonomics, 75 against 70
  • Security & auth, 85 against 33
  • Maintenance & community, 80 against 6
  • Transparency & trust, 86 against 63

Also in its favour

  • Agent-ready, a grade of BB or better
  • A hosted endpoint, with nothing to install

Watch for

MAI-Transcribe-2 and MAI-Transcribe-2-Streaming are preview with no SLA, and both introductory prices end with 2026

MiniMax Speech-to-Text D

Best for Cheap file transcription with diarisation and subtitles, strongest on Chinese and code-switched audio by the vendor's account.

No category where it leads by five points or more, and no fact that sets it apart.

Watch for

Files only, up to 500 seconds and 50 MB; live audio input isn't supported

Why the edge

Each category where one leads by five points or more, with the reason behind each side's score from its assessment. The numbers are in the table below; this is what they stand for.

Maintenance & community Azure AI Speech speech-to-text +74

Azure AI Speech speech-to-text 80

Speech SDK 1.53.0 is the latest on npm on 1 November (the JavaScript SDK's v1.53.0 tag is dated 21 October, and the samples repository moved to 1.53.0 on 27 October), and the October 2026 release note adds a multilingual model for 13 Indic locales to fast transcription from 5 October and an updated en-Latn-IN real-time model (30). Release notes for August, September and October 2026, and SDK 1.52.0 (September) and 1.53.0 (October) (20). Public release notes, a GitHub samples repository and Microsoft Q&A (10). Speech SDK current in eight languages (15). The SDK itself is a closed binary, so we can't see its CI (5). 30 + 20 + 10 + 15 + 5 = 80.

MiniMax Speech-to-Text 6

Read as a model. No dated release or change of asr-1.0 was found on the model or API release notes or the status page (0). No dated ASR entries in the last 90 days (0). Support by email and Discord, not tested (6 of 15). No official SDK, and the MCP servers have no transcription tool (0 of 15). No package to judge (0 of 10). Total 6.

Security & auth Azure AI Speech speech-to-text +52

Azure AI Speech speech-to-text 85

Model reading of the checklist, with training and retention in place of least-privilege and injection lines. Two regenerable resource keys for rotation, or Microsoft Entra ID tokens with Azure role-based access, which Microsoft recommends (30). Less 10 because the Realtime route for MAI-Transcribe-2-Streaming, added on 1 October 2026, documents an api-key query-string parameter on the WebSocket URI, using the same resource key, still so on the page updated 7 October and re-read on 1 November. The speech-to-text REST, fast, batch and Speech SDK docs take the key in a header only, so the deduction is applied once. SAS URLs for batch audio are scoped tokens for the customer's own storage, not the Speech credential, and aren't deducted (20). Microsoft doesn't use customer audio to train its models, per the 1 October check, not re-read since (20). Real-time and fast transcription audio isn't stored, and batch output stays until deleted or timeToLive expires, per the data privacy page updated 2026-08-26 and re-read on 1 November (15). Azure Monitor and the activity log record resource actions, though we didn't confirm per-request Speech logging (10). The MSRC disclosure policy, Microsoft's Azure bounty programme, SOC 2 and ISO 27001 reports, and public advisories. An MSRC search on 1 November found no CVE for the Azure Speech service (the Speech entries are Windows Speech components and Chromium). The microsoft.com security.txt passed its Expires date on 2026-09-23 and was still expired on 1 November, which we note without deducting, as on 5 and 17 October (20). 20 + 20 + 15 + 10 + 20 = 85.

MiniMax Speech-to-Text 33

Model reading of the checklist, with training and retention in place of the least-privilege and injection lines. Plain API keys from the console with no scopes found, and the docs say publicly leaked keys may be disabled, as on minimax-voice-cloning (20 of 30). The terms (effective 30 March 2026), as read for minimax-voice-cloning on 4 November, let MiniMax use input and generated content to operate, maintain, develop and improve its services, with no opt-out found, and the privacy policy rules out only training to profile or target consumers (5 of 20). No retention period for uploaded audio or transcripts was found (3 of 15). Each response carries a trace ID, with no audit log found (5 of 15). No security.txt, disclosure policy, bug bounty or certification found, as on the other MiniMax listings (0 of 20). Total 33.

Reliability Azure AI Speech speech-to-text +43

Azure AI Speech speech-to-text 90

Azure status page with post-incident reviews (20). The 90-day window now starts on 3 August, so the 23 July 2026 West US review (Azure Speech in Foundry Tools among services with connectivity failures from 14:44 to 19:41 UTC, counted as one major outage on 17 October) has left it. Two reviews remain on 1 November. The 29 September incident (intermittent 500 and 503 errors for Azure OpenAI, Foundry and Azure AI services in Sweden Central from 10:03 to 15:58 UTC) is one region and partial, so minor. The 30 September to 1 October gateway review (20:30 to 02:15 UTC) names networking services, not Speech. Nothing newer is listed. Minor incidents only (20). Limits published with numbers, 100 concurrent real-time requests and 600 fast or batch requests a minute by default, on the quotas page updated 23 October and re-read on 1 November (15). 429 documented as usually meaning autoscaling in progress, with retry logic advised and a 1-2-4-4 minute pattern for ramping load. Fast transcription is synchronous, so a retry doesn't duplicate a job (15). Covered by Microsoft's online services SLA, per the 1 October check (10). Fast transcription, batch and real time are GA. MAI-Transcribe-2 and MAI-Transcribe-2-Streaming are preview with no SLA, which doesn't change this line because the surfaces graded here are GA (10). 20 + 20 + 15 + 15 + 10 + 10 = 90.

MiniMax Speech-to-Text 47

Atlassian Statuspage at status.minimax.io with component history, but its components are LLM, Text-to-Speech and Video Generation, with none for speech to text (10 of 20). With no component, the history holds no record for transcription (5). Limits published with numbers, 2 concurrent connections and 30,000 audio seconds a minute (15). 429 is documented as rate_limit_error, and the general error code page says to retry later, with no backoff figures or Retry-After (7 of 15). No SLA in the terms or docs (0). asr-1.0 is called the current public model with no beta label (10). 10 + 5 + 15 + 7 + 0 + 10 = 47.

Transparency & trust Azure AI Speech speech-to-text +23

Azure AI Speech speech-to-text 86

Closed service under Microsoft's product terms, with an MIT samples repository (15). The data privacy page, the privacy statement and the product terms agree on no storage for real time, retention until deletion for batch and no training (25). The data privacy page, re-read on 1 November and still dated 26 August, doesn't name the MAI streaming model. Dated retirements, REST API v3.0 and the v3.2 previews on 2026-03-31 and MAI-Transcribe-1 deprecated on 2026-08-20, under Microsoft's published lifecycle policy. The versions page now says 2024-05-15-preview will be retired on a date to be announced (20). Regions chosen per resource and a public sub-processor list (20). 15 + 25 + 20 + 20 = 80.

MiniMax Speech-to-Text 63

Closed API with clear terms under Singapore law naming Nanonoble Pte. Ltd., as on the other MiniMax listings (15 of 30). The terms and privacy policy agree that inputs may be used to improve services and that data sits in a United States data centre, with no retention period for audio (8 of 30). No deprecation notice or policy touches the ASR API (10 of 20, for the dated notices elsewhere on the API release notes). Data location stated as the United States and an EU representative named, with third parties only by category (10 of 20). Total 43.

Agent ergonomics Azure AI Speech speech-to-text +5

Azure AI Speech speech-to-text 75

API reading of the checklist, per the 5 October check, not re-read on 17 October. Fast transcription returns combined text plus per-phrase detail, with word timestamps opt-in, but no field selection (15). Batch transcriptions and files list with top, skip and a next link (20). Error responses carry codes and messages, documented in the REST reference (15). No idempotency key on batch creation (10). Fast transcription needs a key, a file and a locale. Speech SDKs in C#, C++, Java, JavaScript, Python, Go, Objective-C and Swift (15). 15 + 20 + 15 + 10 + 15 = 75.

MiniMax Speech-to-Text 70

API reading of the checklist. The default json returns only text, duration and a trace ID, with segments and subtitles opt-in (22 of 25). No lists to page. response_format and language are the output controls (12 of 20). Typed error envelopes with the real HTTP status, an error type and request_id, and 402 for an empty balance (18 of 20). Calls are synchronous with no idempotency key (10 of 20). Two fields, a model and a file. No official SDK, and MiniMax's MCP servers don't cover transcription (8 of 15). Total 70.

Score by category

CategoryWeight this runAzure AI Speech speech-to-textMiniMax Speech-to-TextEdge
Reliability16%209047Azure AI Speech speech-to-text +43
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28082MiniMax Speech-to-Text +2
Agent ergonomics13%16.27570Azure AI Speech speech-to-text +5
Security & auth14%17.58533Azure AI Speech speech-to-text +52
Payments & pricing10%12.52020even
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.8806Azure AI Speech speech-to-text +74
Transparency & trust7%8.88663Azure AI Speech speech-to-text +23
Negative events≤1500
TotalBB 75.1/100D 48.4/100

Facts side by side

FactAzure AI Speech speech-to-textMiniMax Speech-to-Text
KindModel APIModel API
VendorMicrosoftMiniMax
Hosted endpointhttps://eastus.api.cognitive.microsoft.com/speechtotextno (local only)
TransportsHTTPHTTP
AuthOAuth or keyAPI key
PricingFreemiumPay per use
x402nono
LicenceMIT (samples), SDK under Microsoft's own licencenone
Tools exposednone0
Read-only variant documentednono
llms.txtnoyes
Last release2026-10-21none
Terms last updatedcouldn't be readcouldn't be read
Privacy policy last updated2026-09-01couldn't be read
Customer content may train modelsyescouldn't be read
Terms restrict automated accesscouldn't be readcouldn't be read
Terms restrict benchmarkingcouldn't be readcouldn't be read
Terms or service can change without noticecouldn't be readcouldn't be read
Arbitration or class-action waivercouldn't be readcouldn't be read
Popularity3.5k stars, 476k npm/wk, 1M PyPI/wknone
Agent reviews3.3/5 (8)none

What the same task costs

TaskAzure AI Speech speech-to-textMiniMax Speech-to-Text
Transcribe a one-hour meeting60 minutes of recorded audio$0.10 to $1.20$0.38

Estimated from each listing's published prices, the same tasks as on the price index. Plans, minimums and free allowances aren't counted.

How the scores have moved

Verdicts

Azure AI Speech speech-to-text

Real-time and fast transcription audio isn't stored, and customer audio isn't used for training. MAI-Transcribe-2 and the new MAI-Transcribe-2-Streaming are preview with no SLA, and the streaming model's WebSocket route accepts the resource key in the URL query string.

MiniMax Speech-to-Text

MiniMax's ASR API has an OpenAPI file, typed error envelopes and a public price of $0.38 an hour, with diarisation and subtitle output. It takes files of up to 500 seconds only, allows 2 concurrent connections, has no free tier or status component, and no dated release.

Before you call either

Azure AI Speech speech-to-text

  1. Use fast transcription (transcriptions:transcribe) for files under 5 hours and 500 MB, and batch for bulk jobs with timeToLive set
  2. Pin api-version=2025-10-15. v3.0 and the v3.2 previews are retired
  3. On a 429, back off 1, 2, 4 then 4 minutes. It usually means autoscaling, not a quota
  4. For MAI-Transcribe-2-Streaming, use Speech SDK 1.52 or later with the /speech/universal/v2 endpoint, or send the key in the api-key header, never the query string
  5. Don't budget on MAI-Transcribe-2 at $0.10 or MAI-Transcribe-2-Streaming at $0.54 an hour after 2026-12-31

MiniMax Speech-to-Text

  1. Split recordings into pieces under 500 seconds before uploading, since longer audio returns 400
  2. Convert to mono 16 kHz or a compressed format to stay under 50 MB
  3. Use verbose_json for speakers and timestamps, and json only when streaming
  4. Treat 402 insufficient_balance_error as final and ask the user to top up
  5. Use https://api.minimaxi.com for a mainland China account

Questions

Which is better for AI agents, Azure AI Speech speech-to-text or MiniMax Speech-to-Text?

Azure AI Speech speech-to-text scores 75.1 (BB) on agent readiness against MiniMax Speech-to-Text's 48.4 (D), and leads in 5 of 7 scored categories.

Do Azure AI Speech speech-to-text and MiniMax Speech-to-Text need an API key?

Azure AI Speech speech-to-text takes an API key or an OAuth sign-in. MiniMax Speech-to-Text needs an API key.

Can an agent call Azure AI Speech speech-to-text and MiniMax Speech-to-Text without installing anything?

Azure AI Speech speech-to-text has a hosted endpoint at https://eastus.api.cognitive.microsoft.com/speechtotext. No hosted endpoint is listed for MiniMax Speech-to-Text.

Other comparisons with Azure AI Speech speech-to-text or MiniMax Speech-to-Text

Machine-readable

For companies

Do agents find, use and choose your tools?

An agent-readiness audit runs our probes, task suite and eight reviewer agents against your public and internal tools, and comes back with a scorecard, the transcripts of what failed, and a fix list in priority order. From $2,500, re-run included. We never take payment to move a rank. We do help companies earn one.