# Gemini 3 Flash vs o3

> Side-by-side benchmark comparison for Gemini 3 Flash and o3 across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/gemini-3-flash-vs-o3
- Last updated: October 17, 2026

- Shared sourced benchmarks: 1
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.8

## Quick Verdict

Evidence is too thin for a benchmark verdict: Gemini 3 Flash and o3 share only 1 sourced benchmark row.

## Summary

- Only 1 shared sourced benchmark row is available. That is not enough for a broad capability verdict, so this mirror does not name an overall winner.
- Gemini 3 Flash has the lower published output-token price.
- Gemini 3 Flash has the larger published context window at 1M.

## Model Snapshot

| Property | Gemini 3 Flash | o3 |
|----------|----------|----------|
| Creator | Google | OpenAI |
| Type | Proprietary | Proprietary |
| Reasoning | Non-Reasoning | Reasoning |
| Context | 1M | 200K |
| Independent public score (not head-to-head) | 54.28 | 45.44 |
| Benchmarks Covered | 11 | 1 |
| Pricing (input/output) | $0.50 / $3.00 | $2.00 / $8.00 |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- Gemini 3 Flash public-lane score: 32.4 (Supported · #88/128)
- o3 public-lane score: Coming soon

| Benchmark | Gemini 3 Flash | o3 | Winner |
|-----------|-----------|-----------|--------|
| Claw-Eval | 49.2% | Coming soon | Coming soon |
| Gert Labs | 56.63% | Coming soon | Coming soon |
| JobBench | 11.4% | Coming soon | Coming soon |
| Terminal-Bench 2.1 (Vals) | 53.9% | Coming soon | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- Gemini 3 Flash public-lane score: 32.1 (Supported · #88/150)
- o3 public-lane score: Coming soon

| Benchmark | Gemini 3 Flash | o3 | Winner |
|-----------|-----------|-----------|--------|
| Vibe Code Bench | 20.20% | Coming soon | Coming soon |
| LiveCodeBench (Vals) | 85.6% | Coming soon | Coming soon |
| SWE-bench (Vals) | 75.0% | Coming soon | Coming soon |

### Reasoning

- Winner: Insufficient shared evidence
- Gemini 3 Flash public-lane score: 63.8 (Unranked · 2 rankable rows)
- o3 public-lane score: 77.2 (Unranked · 2 rankable rows)

### Multimodal & Grounded

- Winner: Insufficient shared evidence
- Gemini 3 Flash public-lane score: 80.3 (Unranked · 1 rankable row)
- o3 public-lane score: 67.8 (Unranked · 1 rankable row)

### Knowledge

- Winner: Insufficient shared evidence
- Gemini 3 Flash public-lane score: 55.7 (Supported · #55/184)
- o3 public-lane score: 48.6 (Estimated · #88/184)

| Benchmark | Gemini 3 Flash | o3 | Winner |
|-----------|-----------|-----------|--------|
| GPQA Diamond (Vals) | 87.9% | Coming soon | Coming soon |
| MMLU-Pro (Vals) | 88.6% | Coming soon | Coming soon |

### Instruction Following

- Winner: Insufficient shared evidence
- Gemini 3 Flash public-lane score: 66.1 (#76/148)
- o3 public-lane score: 87.4 (#38/148)

### Mathematics

- Winner: Insufficient shared evidence
- Gemini 3 Flash public-lane score: 57.4 (Unranked · 2 rankable rows)
- o3 public-lane score: 48.5 (Unranked · 1 rankable row)

| Benchmark | Gemini 3 Flash | o3 | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath v2 (Tiers 1-3) | 51.228% | 33.333% | Gemini 3 Flash |
| FrontierMath v2 (Tier 4) | 17.073% | Coming soon | Coming soon |

## FAQ

### Is there enough evidence to pick between Gemini 3 Flash and o3?

Not yet. The models share only 1 sourced benchmark row, so this mirror reports the available measurements and metadata without naming a broad winner.

### What can I compare safely on this page?

Published pricing, context windows, model type, and individual shared benchmark rows are directly comparable. Independent overall scores and non-overlapping benchmark coverage are labeled separately and should not be read as a controlled head-to-head result.

## Related Comparisons

- [Gemini 3 Flash vs o3-pro](/compare/gemini-3-flash-vs-o3-pro)
- [o3 vs o3-pro](/compare/o3-vs-o3-pro)
- [Gemini 3 Flash vs o3-mini](/compare/gemini-3-flash-vs-o3-mini)
- [o3 vs o3-mini](/compare/o3-vs-o3-mini)

## Explore More

- [Gemini 3 Flash profile](/models/gemini-3-flash)
- [o3 profile](/models/o3)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)