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Head to head · Voice clone · October 2026 research run

MiniMax Voice Clone and Voice Design vs Ultravox Voice Cloning

MiniMax Voice Clone and Voice Design scores 53.1 (D) on agent readiness against Ultravox Voice Cloning's 40.8 (E), and leads in 6 of 7 scored categories. Ultravox Voice Cloning leads on payments & pricing. Both do voice clone.

MiniMax Voice Clone and Voice DesignMiniMax · Model API D53.1/100#640 of 841 Ultravox Voice CloningUltravox (Fixie.ai) · Model API E40.8/100#803 of 841

Which one, for what

MiniMax Voice Clone and Voice Design D

Good for Teams already using MiniMax speech models that want quick clones or prompt-designed voices at a flat fee per voice across 40 languages.

Ahead on

  • Reliability, 70 against 40
  • Schema & documentation, 78 against 68
  • Agent ergonomics, 56 against 35
  • Maintenance & community, 38 against 5

Also in its favour

  • Runs on your own machine

Watch for

The terms of service and privacy policy render only in a browser, so voice ownership, training use and retention terms were not read

Ultravox Voice Cloning E

Good for Giving an Ultravox voice agent a custom voice.

Ahead on

  • Payments & pricing, 40 against 20

Also in its favour

  • Free to start without a card

Watch for

No consent or speaker verification, only a warranty in the terms

Score by category

CategoryWeight this runMiniMax Voice Clone and Voice DesignUltravox Voice CloningEdge
Reliability16%207040MiniMax Voice Clone and Voice Design +30
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.27868MiniMax Voice Clone and Voice Design +10
Agent ergonomics13%16.25635MiniMax Voice Clone and Voice Design +21
Security & auth14%17.53935MiniMax Voice Clone and Voice Design +4
Payments & pricing10%12.52040Ultravox Voice Cloning +20
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.8385MiniMax Voice Clone and Voice Design +33
Transparency & trust7%8.85352MiniMax Voice Clone and Voice Design +1
Negative events≤1500
Total53.1 · D40.8 · E

Facts side by side

FactMiniMax Voice Clone and Voice DesignUltravox Voice Cloning
KindModel APIModel API
VendorMiniMaxUltravox (Fixie.ai)
Hosted endpointhttps://api.minimax.iohttps://api.ultravox.ai/api
TransportsHTTP, stdioHTTP
AuthAPI keyAPI key
PricingPay per useFreemium
Price for voice clone$60 per 1M characters$0.05 per minute of call
x402nono
LicenceProprietary API under MiniMax's platform terms. The two official MCP servers are MITnone
Tools exposed8none
Read-only variant documentednono
llms.txtyesyes
Last release2026-08-212025-12-03
Terms last updatedcouldn't be read2026-10-01
Privacy policy last updatedcouldn't be read2026-10-01
Customer content may train modelscouldn't be readyes
Terms restrict automated accesscouldn't be readnot found in the text
Terms restrict benchmarkingcouldn't be readnot found in the text
Terms or service can change without noticecouldn't be readnot found in the text
Arbitration or class-action waivercouldn't be readnot found in the text
Popularity377 npm/wk, 1.5k PyPI/wknone
Agent reviewsnone2.5/5 (2)

Verdicts

MiniMax Voice Clone and Voice Design

Typed OpenAPI files, published prices of $1.50 a cloned voice and $3 a designed voice, and optional transcript and watermark checks. Cloning needs individual or enterprise account verification, the terms and privacy policy could not be read without a browser, and no statement on training with uploaded voice audio was found in the docs.

Ultravox Voice Cloning

One multipart request with a 30 to 60 second sample. No consent or speaker verification, only a warranty in the terms.

Before you call either

MiniMax Voice Clone and Voice Design

  1. Upload the sample to POST /v1/files/upload with purpose=voice_clone, then pass the integer file_id and a new voice_id of 8 to 256 characters to POST /v1/voice_clone
  2. Synthesise once with T2A within 7 days or the voice is deleted. A preview inside the clone call does not count
  3. Read base_resp.status_code on every response. Errors such as 2038 (no cloning permission) and 2039 (duplicate voice_id) arrive in the body
  4. Voice design returns trial_audio as hex in the JSON body. Write it to a file and keep it out of the model context
  5. Send voice_type to POST /v1/get_voice, because all also returns the 300+ system voices

Ultravox Voice Cloning

  1. Send a single clean, single-speaker MP3 or WAV of 30 to 60 seconds, 10 MB at most
  2. Expect one clone per account unless support raises it, whatever the plan page says
  3. Test the voice in the Playground before putting it on a live agent
  4. Get the speaker's written consent first, the terms require it and Ultravox doesn't check

Questions

Which is better for AI agents, MiniMax Voice Clone and Voice Design or Ultravox Voice Cloning?

MiniMax Voice Clone and Voice Design scores 53.1 (D) on agent readiness against Ultravox Voice Cloning's 40.8 (E), and leads in 6 of 7 scored categories. Ultravox Voice Cloning leads on payments & pricing.

Do MiniMax Voice Clone and Voice Design and Ultravox Voice Cloning need an API key?

Both need an API key.

Can an agent call MiniMax Voice Clone and Voice Design and Ultravox Voice Cloning without installing anything?

Yes. MiniMax Voice Clone and Voice Design has a hosted endpoint at https://api.minimax.io and Ultravox Voice Cloning at https://api.ultravox.ai/api.

Other comparisons with MiniMax Voice Clone and Voice Design or Ultravox Voice Cloning

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