GPT 5.4 vs Grok 4.20 Experimental Beta Reasoning pricing
Side-by-side token pricing for GPT 5.4 (OpenAI) and Grok 4.20 Experimental Beta Reasoning (xAI), plus the total cost at three workload sizes so the crossover point is obvious. Prices refreshed 2026-09-23 00:10 UTC.
| Metric | GPT 5.4 | Grok 4.20 Experimental Beta Reasoning |
|---|---|---|
| Input $/1M tokens | $2.5 | $1.25 |
| Output $/1M tokens | $15 | $2.5 |
| Cached input $/1M | $0.25 | $0.2 |
| Context window | 1.1M | 1M |
| Max output | 128K | 1M |
| Vision | yes | yes |
| Tool calling | yes | yes |
| Cache pricing | yes | yes |
Total cost by workload
| Workload | GPT 5.4 | Grok 4.20 Experimental Beta Reasoning | Cheaper |
|---|---|---|---|
| 1M tokens in · 300K out | $7 | $2 | Grok 4.20 Experimental Beta Reasoning (71% less) |
| 10M tokens in · 3M out | $70 | $20 | Grok 4.20 Experimental Beta Reasoning (71% less) |
| 100M tokens in · 30M out | $700 | $200 | Grok 4.20 Experimental Beta Reasoning (71% less) |
On blended cost (weighted 3:1 toward input), Grok 4.20 Experimental Beta Reasoning comes out cheaper by roughly 50% on input pricing. Pick Grok 4.20 Experimental Beta Reasoning when the workload is price-sensitive and its context window covers your prompts; GPT 5.4 is the one to benchmark if you need vision, reasoning depth, or a different quality profile.
Frequently asked
› Is GPT 5.4 cheaper than Grok 4.20 Experimental Beta Reasoning?
On input pricing, Grok 4.20 Experimental Beta Reasoning is cheaper ($1.25 vs $2.5 per 1M tokens). On blended cost the winner is Grok 4.20 Experimental Beta Reasoning, because output tokens are weighted differently for most workloads.
› Which has the larger context window?
GPT 5.4 offers the larger context (1.1M tokens).
› Do these prices include prompt caching?
Cached input is priced separately where a provider publishes a cache rate; the table above lists it per model so the comparison stays like-for-like.