Grok 4.5 vs Muse Spark 1.1
| Spec | Grok 4.5 | Muse Spark 1.1 |
|---|---|---|
| Respan Index | 46.6 (#40) | 46.6 (#40) |
| Blended price per 1M | $3 | $2 |
| Context window | 500K | 1.0M |
| Input / output per 1M | $2 / $6 | $1.25 / $4.25 |
| Max output | - | - |
| Input | text, vision | text, vision, video, audio |
| Released | 2026-07-08 | 2026-07-09 |
Respan Index by category
Each category is scored 0 to 100, and how far ahead the winner is. Leads under a point are close to even.
| Category | Grok 4.5 | Muse Spark 1.1 |
|---|---|---|
| Coding | 26.6 Grok 4.5 | 26.3 Muse Spark 1.1 |
| Agents | 63.9 Grok 4.5 | 57.7 Muse Spark 1.1 |
| Reasoning | 43.3 Grok 4.5 | 48.1 Muse Spark 1.1 |
| Knowledge & language | 49.7 Grok 4.5 | 54.1 Muse Spark 1.1 |
| Human preference | 54.8 Grok 4.5 | 54.7 Muse Spark 1.1 |
Benchmarks both report
Grok 4.5 leads on 10 of the 18 benchmarks both report. Higher is better. Each score links to where it was published.
| Benchmark | Grok 4.5 | Muse Spark 1.1 |
|---|---|---|
| Chess Puzzles (Epoch AI) | 35% | 34% |
| LMArena Elo | 1465 | 1490 |
| LMArena WebDev (LMArena) | 1553 | 1543 |
| LMArena Vision (LMArena) | 1279 | 1280 |
| LMArena Agent (LMArena) | 0.0079 | -0.0767 |
| APEX-Agents (Mercor) | 56.2% | 31.8% |
| DeepSWE v1.1 (Datacurve) | 53.8% | 53.3% |
| LiveBench Agentic Coding (LiveBench) | 56.5% | 58.5% |
| LiveBench Coding (LiveBench) | 68.6% | 77.2% |
| LiveBench Data Analysis (LiveBench) | 73% | 72.5% |
| LiveBench Instruction Following (LiveBench) | 71.5% | 69.6% |
| LiveBench Language (LiveBench) | 82.8% | 74.3% |
| LiveBench Mathematics (LiveBench) | 90.8% | 87.1% |
| LiveBench Reasoning (LiveBench) | 87.2% | 87.7% |
| SAGE (Vals AI) | 35% | 45.6% |
| SimpleQA Verified | 48.3% | 57.8% |
| Vending-Bench 2 (Andon Labs) | 3887.43 | 6520.48 |
| tau2-bench Banking Knowledge (Sierra) | 47.9% | 40.5% |
FAQ
Is Grok 4.5 better than Muse Spark 1.1?
Grok 4.5 and Muse Spark 1.1 tie on the Respan Index at 46.6. Grok 4.5 leads on 10 of the 18 benchmarks both report.
Which is cheaper, Grok 4.5 or Muse Spark 1.1?
Grok 4.5 lists at $2 input and $6 output per 1M tokens; Muse Spark 1.1 at $1.25 and $4.25. Muse Spark 1.1 is 1.5x cheaper per token at list price.
Which has the larger context window?
Grok 4.5 accepts 500K tokens and Muse Spark 1.1 1.0M tokens.