gemini-3.6-flash vs grok-4.20-0309-reasoning
gemini-3.6-flash is 1.3× cheaper on input than grok-4.20-0309-reasoning.
| gemini-3.6-flash | grok-4.20-0309-reasoning | |
|---|---|---|
| Input / 1M | $1.50 | $2.00 |
| Cached input / 1M | $0.15 | $0.20 |
| Output / 1M | $7.50 | $6.00 |
| Context window | 1M | 2M |
| Max output | 66K | 2M |
| Provider | xAI | |
| Vision | Yes | Yes |
| Tool calling | Yes | Yes |
| Token count | estimated | estimated |
Capability for the money
Independent measurement · Artificial Analysis · read 2026-08-11gemini-3.6-flash and grok-4.20-0309-reasoning are close on price and level on hard reasoning (GPQA Diamond) — either will do.
Hard reasoning
graduate-level science and multi-step analysis
GPQA Diamondgemini-3.6-flash +4.3
Averaged over the benchmarks both models sat, gemini-3.6-flash returns 30.9 points of pass rate per dollar of blended price against 29.5 — the ratio that decides whether the dearer model earns its rate.
Each figure is a pass rate: the share of that test set the model answered correctly, measured by a third party rather than self-reported by the lab. Rows are different tests of different difficulty, so compare a model against the other model, not one row against the next. No published following instructions, coding or tool use score for one of these models, so those lenses are omitted. And a benchmark is not your workload — it narrows the shortlist, it does not pick for you.
Which to pick
- Cheaper input: gemini-3.6-flash
- Cheaper output: grok-4.20-0309-reasoning
- Larger context: grok-4.20-0309-reasoning
- Better at hard reasoning: gemini-3.6-flash (92.8% vs 88.5% on GPQA Diamond)
List price is not production cost. Output length, cache hit rate, retries and task quality move the real number more than the headline rate does — price your own prompt on the token ledger before deciding.
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gemini-3.6-flash detail · grok-4.20-0309-reasoning detail · All Google pricing · All comparisons