GPT-5.6 Terra Paid vs 
Grok 4.5 Paid
GPT-5.6 Terra vs Grok 4.5 compared — price per token, context window, multimodality, openness and which to choose. Full 2026 breakdown.
GPT-5.6 Terra — full profile › · Grok 4.5 — full profile ›
Prices & specs refreshed from live data · olud.ai
Open-model prices = cheapest provider via OpenRouter; official maker rates may be higher.
GPT-5.6 Terra vs Grok 4.5 specs
| Spec | GPT-5.6 Terra | Grok 4.5 |
|---|---|---|
| Maker | OpenAI | xAI |
| Type | Proprietary | Proprietary |
| Context window | 1.1M tokens | 500K tokens |
| Input price | $1.25/M | $2/M |
| Output price | $7.5/M | $6/M |
| Vision / multimodal | Yes | Yes |
| Tool / function calling | Yes | Yes |
| Self-hostable | No (API only) | No (API only) |
| License | Proprietary | Proprietary |
Feature comparison
| Capability | GPT-5.6 Terra | Grok 4.5 |
|---|---|---|
| Open weights (downloadable) | ✗ | ✗ |
| Self-hostable | ✗ | ✗ |
| Runs fully offline | ✗ | ✗ |
| Vision / multimodal | ✓ | ✓ |
| Tool / function calling | ✓ | ✓ |
| 1M+ context window | ✓ | ✗ |
Benchmarks: GPT-5.6 Terra vs Grok 4.5
Independent benchmark scores measured by Artificial Analysis. Higher is better (except latency).
Benchmark data by Artificial Analysis.
How GPT-5.6 Terra and Grok 4.5 score
| Criterion | GPT-5.6 Terra | Grok 4.5 |
|---|---|---|
| Cost-efficiency | 4.0 | 4.0 |
| Context window | 5.0 | 4.5 |
| Openness | 1.5 | 1.5 |
| Self-hosting | 1.0 | 1.0 |
| Multimodality | 5.0 | 5.0 |
Scores come from live data — output price (cost), context length, open vs closed weights (openness & self-hosting) and vision/tool support (multimodality). Raw task quality isn't scored here; it depends on your benchmark — see the verdict.
What each model is
GPT-5.6 Terra Paid
GPT-5.6 Terra is a balanced model in OpenAI's GPT-5.6 series, positioned between the flagship Sol tier and the cost-efficient Luna tier. It is suited for everyday coding, reasoning, and agentic...
Grok 4.5 Paid
Grok 4.5 is SpaceXAI's smartest model with frontier performance on coding, knowledge work, and STEM.
Other models in these families
These variants are tracked but not compared here — one page per family keeps the comparison readable.
Frequently asked questions
GPT-5.6 Terra vs Grok 4.5 — which is cheaper?
Grok 4.5 is cheaper on output ($6/M vs $7.5/M).
Which has the larger context window?
GPT-5.6 Terra offers the larger context window (1.1M tokens).
GPT-5.6 Terra vs Grok 4.5 — which should I pick in 2026?
Choose Grok 4.5 for the lower output price ($6/M vs $7.5/M). Choose GPT-5.6 Terra if you need the larger 1.1M context window.
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