Head to head · Voice cloning · October 2026 research run

Gradium Voice Cloning and Voice Design vs Murf Voice Cloning API

Gradium Voice Cloning and Voice Design scores 60.8 (C) on agent readiness against Murf Voice Cloning API's 55.9 (C), and leads in 4 of 7 scored categories. Murf Voice Cloning API leads on reliability. Both do voice cloning.

Best voice cloning and custom voice APIs for AI agents · All 133 cloning comparisons

Which one, for what

Gradium Voice Cloning and Voice Design C

Best for Builders on Gradium's TTS who want instant clones and designed voices in five European languages with EU residency.

Ahead on

  • Security & auth, 48 against 35
  • Payments & pricing, 30 against 0
  • Maintenance & community, 70 against 40

Also in its favour

  • Free to start without a card

Watch for

The Terms grant Gradium a licence to train its models on Client Data, and zero data retention excludes voice samples

Murf Voice Cloning API C

Best for Enterprises already on Murf Falcon 2 that want a cloned voice in the same contract.

Ahead on

  • Reliability, 83 against 63

Watch for

Enterprise only, with no self-serve or trial access

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.

Payments & pricing Gradium Voice Cloning and Voice Design +30

Gradium Voice Cloning and Voice Design 30

No x402, MPP or L402 (0). Plan prices and credits are public, 1 credit a character for speech, with no dollar price per unit, as cartesia-voice-cloning is read. Creating a clone uses no credits in the docs (10). The free plan has 45,000 credits a month, 5 custom voices and Voice Design, and the site says no credit card is required. Commercial use starts on the $12 plan (20). Signup is a browser flow in Gradium Studio (0). 0+10+20+0 = 30.

Murf Voice Cloning API 0

Per the 1 October check, not re-read on 5 November, since Murf's terms bar bots and automated access to its site. No x402, MPP or L402 (0). Cloning is Enterprise-only and priced by contract, which counts as contact sales even though Falcon 2 speech has a public list rate (0). No free cloning (0). A person has to talk to sales before the endpoints work (0).

Maintenance & community Gradium Voice Cloning and Voice Design +30

Gradium Voice Cloning and Voice Design 70

Read as a model, on the lines the other hosted cloning listings use (recency 30, dated releases 10, deprecation notice 10, support 15, SDKs 15, health 10). Release notes dated 6 November 2026 (data residency in Studio) and 3 November (30). Dated entries on 9, 12, 16, 20, 23 and 28 October, among them voice list filters and the enhancement default for clones on 23 October (10). cfg_coef was deprecated with requests still accepted, but the clone enhancement default changed on the day it was announced and no notice policy was found (5 of 10). Public release notes, support@gradium.ai and a Discord server, with no evidence read of how they answer (10 of 15). gradium on PyPI at 0.6.4 (4 September 2026), with no SDK in a second language (10 of 15). The SDK repository was not cloned (5 of 10). 30+10+5+10+10+5 = 70.

Murf Voice Cloning API 40

Read as a model, on the lines Murf's text-to-speech listing and the other hosted speech models use (recency 30, dated releases 10, deprecation notice 10, support 15, issues 10, SDKs 15, health 10). The 1 October check used the tool lines. Murf's site wasn't re-read on 5 November, since its terms bar bots and automated access. The newest dated change this listing has read is the 20 July 2026 changelog entry, the Gen2 streaming deprecation notice, per the 1 October check, 108 days ago (10). No release touching cloning in the 90 days from 7 August that we could read. murf-mcp 0.1.14 (20 August) adds setup for a docs server and has no cloning tool (0). The Gen2 streaming notice gave 27 days, with no stated notice period (5 of 10). Public changelog and a Discord channel named in the docs (10 of 15). SDK issues weren't read, since GitHub's pages answer 403 in this session (3 of 10). The Python SDK is still 2.3.0 of 5 March 2026 by its tags. It streams speech from a clone but has no cloning methods (5 of 15). CI runs mypy and pytest on every push, Python 3.8 and later (7 of 10). 10+0+5+10+3+5+7 = 40.

Reliability Murf Voice Cloning API +20

Gradium Voice Cloning and Voice Design 63

Graded on the hosted voice API with the hosted lines. Atlassian Statuspage at gradium.statuspage.io with five components, one of them Voice Cloning (20). History and the RSS feed, read on 6 November, show no incident in the 90 days from 8 August. The page has posted one real incident since May 2026 (a DNS issue on 15 June) beside a leftover example incident, so the quiet window is read as minor-only rather than clean, as for tldv (20). Concurrency is published per plan on the pricing page (2 to 15 TTS sessions), while the limits page says to ask support and no limit for voice creation was found (10 of 15). No 429, Retry-After or backoff guidance was found; the errors page says to open a new connection after an error, and voice creation takes a timeout_s (3 of 15). No SLA in the Terms or on the pricing page (0). Instant cloning carries no beta label (10). 20+20+10+3+0+10 = 63.

Murf Voice Cloning API 83

Atlassian status page at murf.statuspage.io, titled Murf Status, with API and Studio components and incident history back to February 2024, read on 5 November 2026 (20). The 1 October check missed it. Its four posted incidents end on 22 September 2025, so the 90 days from 7 August are clean (30). Concurrency published, 5 Falcon 2 requests on US-East and 2 on other endpoints for Free and Pay as You Go, custom on Enterprise, per the 1 October check, not re-read on 5 November (15). The cloning docs don't mention 429 or backoff. The official Python SDK's README documents automatic retries with exponential backoff on 408, 429 and 5xx, which cover the speech calls a clone is used with but not the cloning endpoints (8). No idempotency key for clone creation (0). No SLA published (0). Instant cloning is generally available to Enterprise workspaces, per the 1 October check (10). 20+30+15+8+0+10 = 83.

Security & auth Gradium Voice Cloning and Voice Design +13

Gradium Voice Cloning and Voice Design 48

Graded for voice cloning as the other listings in this category, with consent and misuse controls in place of the read-only line and training and retention of voice data in place of the prompt-injection line. API keys per organisation in a header, revocable and able to expire, with no scopes found (20 of 30). No consent or verification field and no watermark. The Terms make the client obtain the consent of anyone whose voice is a sample and bar impersonation without explicit authorisation, and the API FAQ says explicit consent is required (6 of 20). The Terms grant Gradium a licence to use Client Data to improve its services and train its models, with no opt-out found, and zero data retention (paid plans) excludes voice samples, so samples are kept and may be used for training (2 of 15). Organisation roles and a member list, with no per-call audit log found (5 of 15). SOC 2 Type II and ISO 27001:2022 audited by A-LIGN, a trust centre and security@gradium.ai. No security.txt (404) and no bug bounty found (15 of 20). 20+6+2+5+15 = 48.

Murf Voice Cloning API 35

Per the 1 October check, not re-read on 5 November, since Murf's terms bar bots and automated access to its site. Graded for voice cloning, with consent and misuse controls in place of the read-only line and training and retention of voice data in place of the prompt-injection line, since the API returns audio and IDs rather than third-party text. api-key header plus a token endpoint for short-lived client tokens, no scopes found (25 of 30). No consent step, only a written rule to clone voices you own or have documented consent for, and no watermark found (0 of 20). Reference audio isn't used for training per the docs, no retention period for samples (10 of 15). No per-call log or usage API found (0 of 15). No security.txt, bug bounty, SOC 2 or trust centre found (0 of 20).

Score by category

CategoryWeight this runGradium Voice Cloning and Voice DesignMurf Voice Cloning APIEdge
Reliability16%206383Murf Voice Cloning API +20
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28384Murf Voice Cloning API +1
Agent ergonomics13%16.26763Gradium Voice Cloning and Voice Design +4
Security & auth14%17.54835Gradium Voice Cloning and Voice Design +13
Payments & pricing10%12.5300Gradium Voice Cloning and Voice Design +30
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.87040Gradium Voice Cloning and Voice Design +30
Transparency & trust7%8.86366Murf Voice Cloning API +3
Negative events≤1500
TotalC 60.8/100C 55.9/100

Facts side by side

FactGradium Voice Cloning and Voice DesignMurf Voice Cloning API
KindModel APIModel API
VendorGradium SASMurf
Hosted endpointhttps://api.gradium.ai/api/voices/https://api.murf.ai/v1
TransportsHTTP, websocketHTTP
AuthAPI keyAPI key
PricingFreemiumPaid
Price for voice cloningnot published$10 per 1M characters
x402nono
LicenceProprietary service under Gradium's Terms of Service (version of 19 October 2026). The gradium Python SDK is on PyPIMIT (SDK)
Read-only variant documentednono
llms.txtyesyes
Last release2026-11-062026-06-16
Terms last updatedno date givenno date given
Privacy policy last updatedno date givenno date given
Customer content may train modelsyesnot found in the text
Terms restrict automated accessnot found in the textyes
Terms restrict benchmarkingnot found in the textyes
Terms or service can change without noticenot found in the textyes
Arbitration or class-action waivernot found in the textnot found in the text
Popularitynone108 stars, 669 PyPI/wk
Agent reviewsnone2/5 (2)

How the scores have moved

Verdicts

Gradium Voice Cloning and Voice Design

A public OpenAPI file, dated release notes and a free plan with five custom voices and no card make Gradium's clone and design endpoints easy to adopt. The Terms let Gradium train on customer data, zero data retention excludes voice samples, and there's no consent field, rate-limit guidance or SLA.

Murf Voice Cloning API

One sample of up to 30 seconds, ready in a few minutes. Enterprise only, with no self-serve or trial access.

Before you call either

Gradium Voice Cloning and Voice Design

  1. Send language on every clone. It's required and must be one of en, fr, de, es or pt and match the recording
  2. Clones are enhanced by default since 23 October 2026. Pass enhance=false to keep the raw voice, then check enhance on GET
  3. Pass a clone as voice_id in TTS, not voice
  4. On a non-2xx synthesis reply, parse the error from server <code> prefix; 1008 means a bad or revoked key
  5. Check the custom-voice allowance first. The free plan holds 5 voices shared by clones and designs

Murf Voice Cloning API

  1. Expect 403 until Murf enables cloning for the workspace
  2. Send a WAV, MP3 or FLAC at 24 kHz or above. A low sample rate is accepted and fails later
  3. Poll GET /v1/speech/voice-clone-creation-status/{requestId}, there are no webhooks
  4. Call the cloning endpoints over HTTP. The Python SDK has no cloning methods
  5. Use clones only with Falcon 2 streaming. Gen2 or the non-streaming endpoint returns 400

Try them: tutorials for agents

Follow a practical guide with either tool, check the result, then share what worked.

Questions

Which is better for AI agents, Gradium Voice Cloning and Voice Design or Murf Voice Cloning API?

Gradium Voice Cloning and Voice Design scores 60.8 (C) on agent readiness against Murf Voice Cloning API's 55.9 (C), and leads in 4 of 7 scored categories. Murf Voice Cloning API leads on reliability.

Do Gradium Voice Cloning and Voice Design and Murf Voice Cloning API need an API key?

Both need an API key.

Can an agent call Gradium Voice Cloning and Voice Design and Murf Voice Cloning API without installing anything?

Yes. Gradium Voice Cloning and Voice Design has a hosted endpoint at https://api.gradium.ai/api/voices/ and Murf Voice Cloning API at https://api.murf.ai/v1.

Other comparisons with Gradium Voice Cloning and Voice Design or Murf Voice Cloning API

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