Model comparison
Muse Spark 1.2 vs Muse Spark 1.3
Two Meta tiers compared on the figures that decide which one a workload actually needs.
Catalog record checked September 5, 2026Individual provider fields may changeEvidence confidence: Insufficient data — see receipts below
Meta
Muse Spark 1.2
Frontier
Meta
Muse Spark 1.3
Frontier
| Specification | Muse Spark 1.2 | Muse Spark 1.3 |
|---|---|---|
| Provider | Meta | Meta |
| Tier | Frontier | Frontier |
| Context window | 1M | 1M |
| Max output | Not verifiedUnverified | 131K |
| Input / 1M tokens | Not verifiedUnverified | $1.25 |
| Output / 1M tokens | Not verifiedUnverified | $4.25 |
| Weights | Closed | Closed |
| Parameters | Meta frontier model | Meta frontier model |
| Reasoning levels | low, medium, high | low, medium, high |
| Modalities | text, image | text, image |
| API model id | muse-spark-1.2 | muse-spark-1.3 |
| Released | August 5, 2026 | September 2, 2026 |
| Artificial Analysis Intelligence Index (2026-08-14) | 57 | Not verifiedUnverified |
| DeepSWE 1.1 (2026-09-02) | Not verifiedUnverified | 75.4 |
| Terminal-Bench 2.1 (2026-09-03) | Not verifiedUnverified | 88.8 |
Prices are USD per million tokens at standard rates, excluding batch and caching discounts. Bold indicates the better figure where one is objectively better. Values we could not confirm from the provider are shown as “Not verified” rather than estimated.
Benchmark receipts
- 2026-09-03: Meta launch table (transcribed by explainx.ai) (Vendor self-report; absent from the official tbench.ai leaderboard)Agentic terminal work: multi-step tasks executed in a sandboxed shell environment. Comparability: comparable with caveat — Scores across Terminal-Bench major versions (v1 vs v2) are NOT comparable; harness configuration (container, time limits) also shifts results.
- 2026-09-02: Meta launch table (Thinking mode: max — self-reported; not broadly available and NOT on the official Datacurve leaderboard)Agentic software engineering: pass@1 on real repo tasks with reported cost per completed task. Comparability: directly comparable
- 2026-08-14: Artificial AnalysisComposite index blending reasoning, knowledge, and coding evals into one 0–100 score. Comparability: directly comparable — AA occasionally rebaselines the index scale between snapshots — a score captured on one date is only comparable to same-snapshot scores (check measuredAt).
Pricing tiers: Muse Spark 1.2: Closed-weights; served via Meta's Model API. Not open-weight. · Muse Spark 1.3: $1.25/$4.25 per MTok on Meta's Model API (cached input $0.15); a $0.10/$0.20 'contributor' tier applies when your data is used for training. Third-party reports put list at $1.50/$7.50 from 2027-01-01 — confirm before long-term commits.
Muse Spark 1.2
Muse Spark 1.2 is Meta's closed frontier model until the 1.3 refresh (2026-09-02) — still served and ranked in the LMArena text top 10 as of mid-2026.
Best for
- Frontier reasoning
- Meta ecosystem
- Agentic work
Watch out
Closed-weights (unlike Llama 4); Meta's post-Llama-4 frontier branding.
Muse Spark 1.3
Muse Spark 1.3 is Meta's September 2026 frontier refresh — a self-reported DeepSWE 1.1 field leader at $1.25/$4.25, with a 1M-token context aimed at autonomous agent workflows.
Best for
- Long-horizon coding agents
- Frontier quality below frontier pricing
- Meta ecosystem
Watch out
The headline 75.4% DeepSWE score comes from the 'max' thinking mode, which is not broadly available yet and is pending independent verification. The 131,072 output cap is per third-party API docs — Meta's own spec page does not publish it. Closed weights, unlike Muse Spark 1.1.
When the cheaper one wins
One of these rows is missing a verified output price, so this page will not name a cheaper winner. Run the model picker against the actual job instead of guessing.
Run the model pickerEvidence confidence: Insufficient data
How strong and complete the evidence behind this comparison is — not a prediction of which model is better. Hard limitations apply: missing pricing; evidence too sparse.
- Pricing incomplete — No verified token pricing for Muse Spark 1.2.
- 4/5 core specs verified on both sides — Not published for at least one side: max output.
- No shared named benchmark — No benchmark has been measured on both models.
- Verified within the last 90 days — Newest catalog check was 6 days ago.
- Both models carry source citations — Each side has at least two catalog sources on record.
Source receipts
Each catalog figure was checked against the provider or an independent second source on the date shown.
- Muse Spark 1.2: Meta — Muse (accessed 2026-08-29)
- Muse Spark 1.2: Muse version tracking (accessed 2026-08-29)
- Muse Spark 1.3: Meta — Introducing Muse Spark 1.3 (accessed 2026-09-03)
- Muse Spark 1.3: Meta developer — Muse Spark pricing ($1.25/$4.25) (accessed 2026-09-03)
- Muse Spark 1.3: VentureBeat — Muse Spark 1.3 best results need a config developers can't broadly use yet (accessed 2026-09-03)
- Muse Spark 1.3: HaiMaker — muse-spark-1.3 (131,072 max output tokens) (accessed 2026-09-05)
- Muse Spark 1.3: Promptfoo — Meta provider docs (muse-spark-1.3 max_tokens ceiling) (accessed 2026-09-05)
Related comparisons
- Claude Fable 5.1 vs Muse Spark 1.2
- Claude Fable 5.1 vs Muse Spark 1.3
- Claude Fable 5 vs Muse Spark 1.2
- Claude Fable 5 vs Muse Spark 1.3
- Claude Mythos 5.1 vs Muse Spark 1.2
- Claude Mythos 5.1 vs Muse Spark 1.3
Diving deeper on one model? Muse Spark 1.2 · Muse Spark 1.3
Common questions
Muse Spark 1.2 vs Muse Spark 1.3
Answered from the verified figures on this page rather than general guidance.
Which has the larger context window, Muse Spark 1.2 or Muse Spark 1.3?
Both accept about 1M tokens of context, so document length will not decide between them.
Do Muse Spark 1.2 and Muse Spark 1.3 support the same reasoning levels?
Yes — both accept the same effort settings: "low", "medium", "high". Higher effort costs more and takes longer, so start low and raise it only where output quality actually improves.
Should I use Muse Spark 1.2 or Muse Spark 1.3?
Both sit in the frontier tier, so the choice usually comes down to price and context rather than capability. Muse Spark 1.2 suits frontier reasoning; Muse Spark 1.3 suits long-horizon coding agents.
Next step
Choosing between them
The verified figures that separate this pair, computed from the catalog rather than restated boilerplate.
These two models match on every verified catalog figure — the decision comes down to provider preference, availability, and workload fit rather than published numbers.
Choosing a harness rather than a model — Cursor, Copilot, Claude Code, Windsurf, or Lovable? Compare agentic harnesses · Latest releases.