Side-by-side comparison of pricing, 12 benchmarks, and generation speed.
| Metric | Celeris-1 | Grok 4.5 (high) |
|---|---|---|
| Input ($/M tokens) | $2 | $2 |
| Output ($/M tokens) | $6 | $6 |
Verdict. Grok 4.5 (high) takes the aggregate benchmark matchup 5–0 across 5 categories. Real workloads usually care about a handful of specific tasks — see the per-benchmark table above.
Pricing. Both models sit in the mid-tier bracket for output-token pricing. At 1.0× the per-million-token cost, Grok 4.5 (high) is meaningfully cheaper if your traffic is output-heavy (long completions, document generation, agent loops). Grok 4.5 (high) makes more sense when output volume is low and absolute reasoning quality justifies the premium.
Strengths. Celeris-1 is strongest on GPQA Diamond (63%), SciCode (21%), Coding Index (14.4). Grok 4.5 (high) leads on GPQA Diamond (93%), Coding Index (72.4), SciCode (54%).
Speed. On throughput, Celeris-1 generates tokens at 2195 tok/s versus 59 tok/s — about 97% faster. On time-to-first-token, Celeris-1 responds in 482ms vs 12902ms, which matters most for chat-style UIs.
Provider. Celeris and SpaceXAI sell to overlapping but distinct developer audiences: Celeris tends to ship frontier reasoning models with premium positioning, while SpaceXAI often prices more aggressively. Your existing vendor relationships, billing, and SLA preferences may matter as much as the raw numbers above.
Workload cost. Workload scenarios (per million requests at 30M input + 15M output tokens): Celeris-1 costs $150.00 ($1800/year); Grok 4.5 (high) costs $150.00 ($1800/year). At a smaller 5M-input/2M-output scale (single-developer tool or prototype): Celeris-1 ≈ $22.00/run, Grok 4.5 (high) ≈ $22.00/run. At agent/realtime scale (200M input / 100M output per million requests): Celeris-1 ≈ $1000/run, Grok 4.5 (high) ≈ $1000/run.
Recommendation. Both models have legitimate use cases — the right answer depends on whether you are optimizing for benchmark ceiling, latency, or unit cost. Start with the cheaper / faster model, evaluate against your specific task, and only switch if the upgrade shows a meaningful lift.
Head-to-head deltas
Data from Artificial Analysis API — 12 benchmarks
Both models have similar pricing. Check the detailed breakdown above for input vs output token costs.
Grok 4.5 (high) wins 5 out of 12 benchmarks compared to 0 for Celeris-1. See the detailed benchmark chart above for per-category results.
Celeris-1 generates tokens faster at 2195 tok/s vs 59 tok/s. Celeris-1 also has lower time-to-first-token (0.48s vs 12.90s).
Choose based on your priorities: both are similarly priced, Grok 4.5 (high) for stronger benchmark performance, and Celeris-1 for faster generation. For latency-sensitive apps, check the TTFT comparison above.