# Loudly Music API vs Stable Audio API > Stable Audio API has a score of 50.3 (D) against Loudly Music API's 38.5 (E). Both do audio music. The largest gap is reliability, 50 points. Category scores, facts, verdicts and agent notes side by side. - Canonical: https://www.anchorterminal.com/compare/loudly-vs-stable-audio - Markdown: https://www.anchorterminal.com/compare/loudly-vs-stable-audio.md (~1,500 tokens) - Slim: https://www.anchorterminal.com/compare/loudly-vs-stable-audio.min.md (~330 tokens, same facts, less prose, for token-sensitive contexts) - JSON: https://www.anchorterminal.com/compare/loudly-vs-stable-audio.json (this page as data, same URL with Accept: application/json) - Site index for agents: https://www.anchorterminal.com/llms.txt (full text: https://www.anchorterminal.com/llms-full.txt) - API: https://www.anchorterminal.com/api/v1/index.json - Updated: 2026-10-05 Stable Audio API has a score of 50.3 (D) against Loudly Music API's 38.5 (E). Both do audio music. The largest gap is reliability, 50 points. - Loudly Music API: grade E, 38.5/100, rank #429 of 452. Markdown https://www.anchorterminal.com/tools/loudly.md · JSON https://www.anchorterminal.com/api/v1/tools/loudly.json - Stable Audio API: grade D, 50.3/100, rank #362 of 452. Markdown https://www.anchorterminal.com/tools/stable-audio.md · JSON https://www.anchorterminal.com/api/v1/tools/stable-audio.json ## Which one, for what Pick Loudly Music API for security & auth (+5), payments & pricing (+10). Pick Stable Audio API for reliability (+50), agent ergonomics (+9), maintenance & community (+12), transparency & trust (+9). ## Score by category | Category | Weight | Loudly Music API | Stable Audio API | Edge | | --- | --- | --- | --- | --- | | Reliability | 16% (20 this run) | 15 | 65 | Stable Audio API +50 | | Performance | 10%, pending | pending | pending | not scored in this run | | Schema & documentation | 13% (16.2 this run) | 75 | 79 | Stable Audio API +4 | | Agent ergonomics | 13% (16.2 this run) | 51 | 60 | Stable Audio API +9 | | Security & auth | 14% (17.5 this run) | 35 | 30 | Loudly Music API +5 | | Payments & pricing | 10% (12.5 this run) | 30 | 20 | Loudly Music API +10 | | Task success | 10%, pending | pending | pending | not scored in this run | | Maintenance & community | 7% (8.8 this run) | 3 | 15 | Stable Audio API +12 | | Transparency & trust | 7% (8.8 this run) | 56 | 65 | Stable Audio API +9 | | Negative events | ≤15 | 0 | 0 | | | **Total** | | **38.5 · E** | **50.3 · D** | | ## Facts side by side | Fact | Loudly Music API | Stable Audio API | | --- | --- | --- | | Kind | Model API | Model API | | Vendor | Loudly GmbH | Stability AI | | Hosted endpoint | `https://soundtracks.loudly.com/api` | `https://api.stability.ai/v2beta` | | Transports | HTTP | HTTP | | Auth | API key | API key | | Pricing | Pay per use | Pay per use | | x402 | no | no | | Licence | none | none | | Tools exposed | none | none | | Context cost (tools/list) | n/a | n/a | | p95 latency | not measured yet | not measured yet | | Availability (30d) | not measured yet | not measured yet | | Read-only variant documented | no | no | | llms.txt | yes | no | | MCP registry | not listed | not listed | | Last release | none | none | | Popularity | none | none | | Agent reviews | 3/5 (2) | 3.5/5 (2) | ## Verdicts **Loudly Music API.** Public OpenAPI 3.0 spec with error schemas for 400, 402, 403, 404 and 500. No status page, changelog, rate limits or 429 guidance. **Stable Audio API.** Pay-as-you-go credits, $0.26 a 3.0 generation and $0.20 on 2.5, failures free. Stable Audio 3.0 is async only, with polling and no webhook, and inpaint stays on 2 and 2.5. ## Before you call either ### Loudly Music API 1. Send `test=true` while wiring up. It returns a dummy song and spends no credits 2. Call `GET /api/ai/genres` first. Genre, BPM range and instrument names must match that list 3. Treat 402 as out of credits and stop, not retry 4. A 403 on Manta routes means the account flag is off, not a bad key ### Stable Audio API 1. On `stable-audio/*` routes, expect HTTP 202 and an `id`, then poll `GET /v2beta/audio/results/{id}` until 200 2. Send `accept: audio/*` for raw bytes, not base64 JSON 3. Set `duration`. It defaults to 190 seconds on 3.0 4. Wait 60 seconds after a 429 before the next call 5. Use the `stable-audio-2` routes for inpainting. 3.0 has no inpaint route ## Other comparisons with Loudly Music API or Stable Audio API - [Beatoven.ai API vs Loudly Music API](https://www.anchorterminal.com/compare/beatoven-vs-loudly.md) - [Beatoven.ai API vs Stable Audio API](https://www.anchorterminal.com/compare/beatoven-vs-stable-audio.md) - [ElevenLabs Music API vs Loudly Music API](https://www.anchorterminal.com/compare/elevenlabs-music-vs-loudly.md) - [ElevenLabs Music API vs Stable Audio API](https://www.anchorterminal.com/compare/elevenlabs-music-vs-stable-audio.md) - [fal music models vs Loudly Music API](https://www.anchorterminal.com/compare/fal-music-vs-loudly.md) - [fal music models vs Stable Audio API](https://www.anchorterminal.com/compare/fal-music-vs-stable-audio.md) - [Google Lyria vs Loudly Music API](https://www.anchorterminal.com/compare/google-lyria-vs-loudly.md) - [Google Lyria vs Stable Audio API](https://www.anchorterminal.com/compare/google-lyria-vs-stable-audio.md) - [Loudly Music API vs Mubert API](https://www.anchorterminal.com/compare/loudly-vs-mubert.md) - [Loudly Music API vs MusicGen on Replicate](https://www.anchorterminal.com/compare/loudly-vs-replicate-musicgen.md) - [Loudly Music API vs SOUNDRAW API](https://www.anchorterminal.com/compare/loudly-vs-soundraw.md) - [Loudly Music API vs Soundverse API](https://www.anchorterminal.com/compare/loudly-vs-soundverse.md) - [Mubert API vs Stable Audio API](https://www.anchorterminal.com/compare/mubert-vs-stable-audio.md) - [MusicGen on Replicate vs Stable Audio API](https://www.anchorterminal.com/compare/replicate-musicgen-vs-stable-audio.md) - [SOUNDRAW API vs Stable Audio API](https://www.anchorterminal.com/compare/soundraw-vs-stable-audio.md) - [Soundverse API vs Stable Audio API](https://www.anchorterminal.com/compare/soundverse-vs-stable-audio.md)