Math
Like-for-like- Gemini 3.5 Flash
- 32.9
- o3
- 14.5
- Weighted basis
- 2 vs 2 rows
- Reading
- Gemini 3.5 Flash leads
Gemini 3.5 Flash vs o3
Updated August 18, 2026. Public scores include evidence status and uncertainty. They are not guarantees for a specific workload.
Decision reading
Gemini 3.5 Flash has the higher public score, 64.67 versus 47.01, and the 90% score intervals do not overlap.
2 results are shared. Category rows based on different benchmark sets are marked directional and do not name a winner.
Which one for your work
Recommendations appear only when a shared evidence basis or an explicit operating constraint supports the call. Secondary and unsupported use cases stay disclosed below the initial list.
Long documents
Prompts that approach the documented context limit
Gemini 3.5 Flash
Gemini 3.5 Flash has the larger documented context window.
Confidence: documented
Show secondary and unsupported calls
Repository review cost
50K fresh input + 3K output tokens
Gemini 3.5 Flash
Gemini 3.5 Flash has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
Coding work
Code generation, repair, and software-engineering tasks
Not enough matched evidence
No shared weighted benchmark basis supports a winner.
Confidence: limited
Agentic work
Tool use, computer use, and multi-step task completion
Not enough matched evidence
No shared weighted benchmark basis supports a winner.
Confidence: limited
Chat turn cost
1K fresh input + 500 output tokens
No clear pick
A complete comparable API-rate estimate is not available for both models.
Confidence: listed-rates
Cache-heavy agent loop cost
200K cached + 20K fresh input + 10K output tokens
Not enough matched evidence
The page does not recommend a cost winner because at least one model cannot fit the stated workload in one request. o3 does not fit this workload in one request. o3 has no published cached-input rate, so cached tokens use its listed input rate.
Confidence: rate-fallback
What is actually comparable
Shared results can support a head-to-head reading. Results present for only one model describe coverage, not superiority.
21 Gemini 3.5 Flash only
2 Shared
- Shared results
- 2
- Gemini 3.5 Flash only
- 21
- o3 only
- 0
- Like-for-like categories
- 1 / 8
Category results, on a stated basis
Each row states whether both averages use the same weighted benchmark set. Directional and not-comparable rows remain visible, but they never receive a winner in this template.
Agentic
Not comparable- Gemini 3.5 Flash
- 77.2
- o3
- Not measured
- Weighted basis
- 2 vs 0 rows
- Reading
- Not comparable
Coding
Not comparable- Gemini 3.5 Flash
- 55.1
- o3
- Not measured
- Weighted basis
- 1 vs 0 rows
- Reading
- Not comparable
Reasoning
Not comparable- Gemini 3.5 Flash
- 74.7
- o3
- Not measured
- Weighted basis
- 2 vs 0 rows
- Reading
- Not comparable
Knowledge
Not comparable- Gemini 3.5 Flash
- 40.2
- o3
- Not measured
- Weighted basis
- 1 vs 0 rows
- Reading
- Not comparable
Multilingual
Not comparable- Gemini 3.5 Flash
- Not measured
- o3
- Not measured
- Weighted basis
- 0 vs 0 rows
- Reading
- Not comparable
Multimodal
Not comparable- Gemini 3.5 Flash
- 83.8
- o3
- Not measured
- Weighted basis
- 2 vs 0 rows
- Reading
- Not comparable
Instruction following
Not comparable- Gemini 3.5 Flash
- Not measured
- o3
- Not measured
- Weighted basis
- 0 vs 0 rows
- Reading
- Not comparable
| Category | Gemini 3.5 Flash | o3 | Weighted basis | Reading |
|---|---|---|---|---|
| Math | 32.9 | 14.5 | Like-for-like2 vs 2 rows | Gemini 3.5 Flash leads |
| Agentic | 77.2 | Not measured | Not comparable2 vs 0 rows | Not comparable |
| Coding | 55.1 | Not measured | Not comparable1 vs 0 rows | Not comparable |
| Reasoning | 74.7 | Not measured | Not comparable2 vs 0 rows | Not comparable |
| Knowledge | 40.2 | Not measured | Not comparable1 vs 0 rows | Not comparable |
| Multilingual | Not measured | Not measured | Not comparable0 vs 0 rows | Not comparable |
| Multimodal | 83.8 | Not measured | Not comparable2 vs 0 rows | Not comparable |
| Instruction following | Not measured | Not measured | Not comparable0 vs 0 rows | Not comparable |
Shape of the matched evidence
Only shared public evidence is shown. Sparse evidence stays a ruled list rather than being closed into a radar shape.
Too few matched category axes support a radar. The ruled list below shows only shared benchmark results; positions use each benchmark’s normalized display scale when available.
FrontierMath v2 (Tiers 1-3)
Math
FrontierMath v2 (Tier 4)
Math
What each workload costs
Three fixed token mixes turn per-token rates into comparable decisions. Each scenario states context fit and whether cached input had to fall back to the published list-input rate.
Chat turn
1K fresh input + 500 output tokens
- Gemini 3.5 Flash
- $0.006
- Fits in one request
- o3
- $0.006
- Fits in one request
Modeled costs are equal
Costs use the listed standard API rates.
Repository review
50K fresh input + 3K output tokens
- Gemini 3.5 Flash
- $0.102
- Fits in one request
- o3
- $0.124
- Fits in one request
Gemini 3.5 Flash has the lower modeled cost
Costs use the listed standard API rates.
Cache-heavy agent loop
200K cached + 20K fresh input + 10K output tokens
- Gemini 3.5 Flash
- $0.15
- Fits in one request
- o3
- $0.52
- Does not fit in one request
- Cached input priced at the published list-input rate
o3 does not fit this workload in one request. o3 has no published cached-input rate, so cached tokens use its listed input rate.
Specification differences
Sourced differences are shown directly. Missing facts stay explicit instead of being inferred from a model name or family.
SpecificationGemini 3.5 Flasho3
Context window
Maximum documented context; output-token limits may be lower.
Gemini 3.5 Flash
o3
200K
API model ID
Gemini 3.5 Flash
gemini-3.5-flash
Google Gemini API pricingo3
Not sourced
Cached-input rate
A missing cached-input rate falls back to the listed input rate only in the stated workload estimate.
Gemini 3.5 Flash
$0.15 per 1M cached input tokens
Google Gemini API pricingo3
Not published
Documented inputs
Gemini 3.5 Flash
Not sourced
o3
Not sourced
Documented outputs
Gemini 3.5 Flash
Not sourced
o3
Not sourced
Provider availability
Gemini 3.5 Flash
Not sourced
o3
Not sourced
Reasoning profile
Gemini 3.5 Flash
Reasoning
o3
Reasoning
Weight access
Gemini 3.5 Flash
Proprietary
o3
Proprietary
License
Gemini 3.5 Flash
Proprietary
o3
Proprietary
Release date
Gemini 3.5 Flash
2026-05-19
o3
2025-04-16
If you already use one of these models
- Deployment change
- The models list different providers, so authentication, endpoint behavior, limits, and feature support may change.
- Quality signal
- Gemini 3.5 Flash has the higher public score, 64.67 versus 47.01, and the 90% score intervals do not overlap.
- Workload cost
- Repository review: $0.102 vs $0.124. Cache-heavy agent loop: $0.15 vs $0.52.
- Context tradeoff
- Gemini 3.5 Flash has the larger documented window (1M).
Run the same representative tasks against both endpoints before changing production traffic.
Benchmark evidence
The full public result ledger is available for audit without forcing a wide desktop table onto a phone.
Browse raw public benchmark evidence23 rows
Agentic
Terminal-Bench 2.0
Gemini 3.5 Flash76.2%Sourceo3—Not directly comparable
MCP Atlas
Gemini 3.5 Flash83.6%Sourceo3—Not directly comparable
Toolathlon
Gemini 3.5 Flash56.5%Sourceo3—Not directly comparable
OSWorld-Verified
Gemini 3.5 Flash78.4%Sourceo3—Not directly comparable
Finance Agent v2
Gemini 3.5 Flash57.9%Sourceo3—Not directly comparable
Gert Labs
Gemini 3.5 Flash61.85%Sourceo3—Not directly comparable
ResearchClawBench
Gemini 3.5 Flash18.0%Sourceo3—Not directly comparable
Coding
Terminal-Bench 2.0
Gemini 3.5 Flash76.2%Sourceo3—Not directly comparable
SWE-bench Pro
Gemini 3.5 Flash55.1%Sourceo3—Not directly comparable
Vibe Code Bench
Gemini 3.5 Flash48.68%Sourceo3—Not directly comparable
cursorBench31
Gemini 3.5 Flash49.8%Sourceo3—Not directly comparable
cursorBench32
Gemini 3.5 Flash48.8%Sourceo3—Not directly comparable
EEBench
Gemini 3.5 Flash34.3%Sourceo3—Not directly comparable
Reasoning
Knowledge
Math
FrontierMath v2 (Tiers 1-3)
Shared sourceGemini 3.5 Flash38.966%o318.685%Gemini 3.5 Flash leads this result
FrontierMath v2 (Tier 4)
Shared sourceGemini 3.5 Flash14.583%o32.083%Gemini 3.5 Flash leads this result
Multimodal
Frequently asked questions
Which is better, Gemini 3.5 Flash or o3?
Gemini 3.5 Flash has the higher public score, 64.67 versus 47.01, and the 90% score intervals do not overlap. That is the clearest overall quality signal in the current public data.
Which is better for coding, Gemini 3.5 Flash or o3?
The published evidence does not provide a shared weighted coding basis for both models, so BenchLM does not name a coding winner.
Which is better for agentic tasks, Gemini 3.5 Flash or o3?
The published evidence does not provide a shared weighted agentic tasks basis for both models, so BenchLM does not name a agentic tasks winner.
Which costs less, Gemini 3.5 Flash or o3?
For the stated presets, chat costs $0.006 on Gemini 3.5 Flash and $0.006 on o3; repository review costs $0.102 and $0.124; the cache-heavy agent loop costs $0.15 and $0.52. o3 does not fit this workload in one request. o3 has no published cached-input rate, so cached tokens use its listed input rate.
Which has the larger context window, Gemini 3.5 Flash or o3?
Gemini 3.5 Flash has the larger documented context window: 1M, compared with 200K.
Related comparisons
Last updated August 18, 2026
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