$ diff grok-4-5 muse-spark
Grok 4.5 vs Muse Spark
xAI and Meta AI, side by side. Every value below is the one recorded on the model’s own wiki page, with its citation — nothing is estimated.
xAIGrok 4.5
- context
- 500K
- weights
- —
- $/M in
- $2
- $/M out
- $6
- context
- 1M
- weights
- open
- $/M in
- $1.25
- $/M out
- $4.25
What actually differs
- Context window
- Muse Spark takes 1M against 500K — 2× more room in a single request.
- Input price
- Muse Spark at $1.25/M against $2/M — 1.6× cheaper to feed.
- Output price
- Muse Spark at $4.25/M against $6/M — 1.4× cheaper to generate. Output dominates the bill on most agentic workloads, where the model writes far more than it reads.
- Recency
- Grok 4.5 shipped 92 days after Muse Spark (2026-07-09 vs 2026-04-08).
Full spec
| Attribute | Grok 4.5 | Muse Spark |
|---|---|---|
| Developer | xAI | Meta AI |
| Released | 2026-07-09 | 2026-04-08 |
| Context window | 500K tokens | 1,000,000 tokens (1.1) |
| Pricing | $2/M input · $6/M output | $1.25/M input · $4.25/M output (Meta Model API, public preview) |
| License | not recorded | proprietary (closed / API-only, not open-weights) |
| Availability | Grok Build (default model), Cursor (all plans), SpaceXAI console/API; not in EU (regulatory review pending as of 2026-07-09) | Meta Model API (public preview, US-based developers only) |
Values come from Grok 4.5 and Muse Spark, where each is cited to its source. This page states no benchmark result and ranks neither model — it puts two published specifications next to each other. Where a lab has not published a figure, the row says so rather than guessing. How these pages are produced.