Model comparison
Gemini 3.6 Flash vs Grok 4.5
Google against xAI, compared on context, price, and verified benchmark results.
Catalog record checked September 5, 2026Individual provider fields may changeEvidence confidence: High — see receipts below
Gemini 3.6 Flash
Balanced
xAI
Grok 4.5
Balanced
| Specification | Gemini 3.6 Flash | Grok 4.5 |
|---|---|---|
| Provider | xAI | |
| Tier | Balanced | Balanced |
| Context window | Winner: 1M | 500K |
| Max output | 64K | Winner: 131K |
| Input / 1M tokens | Winner: $0.75 | $2 |
| Output / 1M tokens | Winner: $3.75 | $6 |
| Weights | Closed | Closed |
| Parameters | Not disclosedUnverified | Not disclosedUnverified |
| Reasoning levels | low, medium, high | low, medium, high |
| Modalities | text, image, video, audio, pdf | text, image |
| API model id | gemini-3.6-flash | grok-4.5 |
| Released | July 21, 2026 | July 8, 2026 |
| Artificial Analysis Intelligence Index (2026-08-14) | 54 | Not verifiedUnverified |
| Artificial Analysis Intelligence Index [high] (2026-08-14) | Not verifiedUnverified | 56 |
| Terminal-Bench 2.1 (2026-07) | 78 | Winner: 83.3 |
| DeepSWE 1.1 (2026-07) | 48.6 | Winner: 54 |
| Humanity's Last Exam (2026-08) | 51.2 | Not verifiedUnverified |
Prices are USD per million tokens at standard rates, excluding batch and caching discounts. Bold indicates the better figure where one is objectively better. Values we could not confirm from the provider are shown as “Not verified” rather than estimated.
Benchmark receipts
- 2026-08-14: Artificial AnalysisComposite index blending reasoning, knowledge, and coding evals into one 0–100 score. Comparability: directly comparable — AA occasionally rebaselines the index scale between snapshots — a score captured on one date is only comparable to same-snapshot scores (check measuredAt).
- 2026-08: Google DeepMind model evaluation report (vendor, HLE-Verified full set)Frontier-knowledge ceiling: extremely hard multi-domain questions written to be near-impossible without deep expertise. Comparability: comparable with caveat — Subset/tool configurations (text-only vs with-tools) differ between vendors and materially change scores; must match configuration to compare.
- 2026-07-16: xAI — Introducing Grok 4.5 (vendor; Datacurve-run)Agentic terminal work: multi-step tasks executed in a sandboxed shell environment. Comparability: comparable with caveat — Scores across Terminal-Bench major versions (v1 vs v2) are NOT comparable; harness configuration (container, time limits) also shifts results.
- 2026-07: Google DeepMind 3.6 Flash evaluation report (independent tabulation; conflicts with xAI's 53 — both preserved)Agentic terminal work: multi-step tasks executed in a sandboxed shell environment. Comparability: comparable with caveat — Scores across Terminal-Bench major versions (v1 vs v2) are NOT comparable; harness configuration (container, time limits) also shifts results.
Pricing tiers: Gemini 3.6 Flash: $0.75/$3.75 per MTok (intro through 2026-12-31, then $1.50/$7.50). Multimodal input. · Grok 4.5: $2/$6 per MTok (<200K prompt); $4/$12 (≥200K). Cached input $0.30/MTok.
Gemini 3.6 Flash
Gemini 3.6 Flash is Google's balanced multimodal Flash tier with a 1M-token context.
Best for
- Multimodal pipelines
- High-volume processing
- Video and audio input
Watch out
Superseded by 3.7 Flash on quality; still a solid mid-tier.
Grok 4.5
Grok 4.5 is xAI's balanced model with a 500K context and real-time X integration.
Best for
- Real-time data queries
- Technical tasks
- Cost-sensitive reasoning
Watch out
A step behind Grok 4.6; 500K context is smaller than the 1M-class models.
When the cheaper one wins
Gemini 3.6 Flash is cheaper on output at $3.75 per million tokens against $6 for Grok 4.5 — about 1.6×. Use the cheaper tier for classification, extraction, summarisation, and any task where the expensive model’s extra score does not change the accepted output. The expensive one only pays if your hardest task actually fails on the cheap tier. These are standard-tier API rates, excluding batch and cache discounts.
Run the model pickerEvidence confidence: High
How strong and complete the evidence behind this comparison is — not a prediction of which model is better.
- Pricing verified on both sides — Input and output rates are verified for both models.
- 4/5 core specs verified on both sides — Not published for at least one side: parameter count.
- 3 shared named benchmarks with differing scores — Measured on: Artificial Analysis Intelligence Index, Terminal-Bench 2.1, DeepSWE 1.1.
- Verified within the last 90 days — Newest catalog check was 6 days ago.
- Both models carry source citations — Each side has at least two catalog sources on record.
Source receipts
Each catalog figure was checked against the provider or an independent second source on the date shown.
- Gemini 3.6 Flash: Google — Gemini 3.6 Flash (accessed 2026-08-29)
- Gemini 3.6 Flash: Google Cloud Gemini pricing (accessed 2026-08-29)
- Grok 4.5: xAI — Introducing Grok 4.5 (public launch 8 Jul 2026; formal announcement 16 Jul) (accessed 2026-08-29)
- Grok 4.5: xAI pricing (grok-4.5 $2/$6, 500K) (accessed 2026-08-29)
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Diving deeper on one model? Gemini 3.6 Flash · Grok 4.5
Common questions
Gemini 3.6 Flash vs Grok 4.5
Answered from the verified figures on this page rather than general guidance.
Is Gemini 3.6 Flash or Grok 4.5 cheaper for input?
Gemini 3.6 Flash is cheaper at $0.75 per million input tokens, against $2 for Grok 4.5 — roughly 2.7× the price. Output tokens usually dominate a real bill, so weigh the output rate more heavily than the input rate. These are base rates; Gemini 3.6 Flash has tiered pricing: $0.75/$3.75 per MTok (intro through 2026-12-31, then $1.50/$7.50). Multimodal input. Grok 4.5 has tiered pricing: $2/$6 per MTok (<200K prompt); $4/$12 (≥200K). Cached input $0.30/MTok.
Is Gemini 3.6 Flash or Grok 4.5 cheaper for output?
Gemini 3.6 Flash is cheaper at $3.75 per million output tokens, against $6 for Grok 4.5 — roughly 1.6× the price. Output tokens usually dominate a real bill, so weigh the output rate more heavily than the input rate. These are base rates; Gemini 3.6 Flash has tiered pricing: $0.75/$3.75 per MTok (intro through 2026-12-31, then $1.50/$7.50). Multimodal input. Grok 4.5 has tiered pricing: $2/$6 per MTok (<200K prompt); $4/$12 (≥200K). Cached input $0.30/MTok.
Which has the larger context window, Gemini 3.6 Flash or Grok 4.5?
Gemini 3.6 Flash accepts 1M tokens against 500K for Grok 4.5. This only matters if you routinely send very long documents or large codebases.
Do Gemini 3.6 Flash and Grok 4.5 support the same reasoning levels?
Yes — both accept the same effort settings: "low", "medium", "high". Higher effort costs more and takes longer, so start low and raise it only where output quality actually improves.
Should I use Gemini 3.6 Flash or Grok 4.5?
Both sit in the balanced tier, so the choice usually comes down to price and context rather than capability. Gemini 3.6 Flash suits multimodal pipelines; Grok 4.5 suits real-time data queries.
Next step
Choosing between them
The verified figures that separate this pair, computed from the catalog rather than restated boilerplate.
- Input price: Gemini 3.6 Flash costs $0.75 per 1M tokens versus $2 for Grok 4.5 — a 2.7x difference at the headline tier.
- Context: Gemini 3.6 Flash takes 1M against 500K for Grok 4.5 — only decisive if your prompts approach the smaller window.
- Measured capability: Grok 4.5 leads Artificial Analysis Intelligence Index 56 to 54 (measured 2026-08-14).
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