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Every score has a dated snapshot.

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  3. Claude Opus 4.8 vs Gemini 3 Flash

Pairwise benchmark snapshot · Aug 17, 2026

Claude Opus 4.8 vs Gemini 3 Flash benchmark

In this head-to-head showdown, Claude Opus 4.8 delivers higher overall intelligence and human-preferred responses (Elo 1,598 vs 1,495), while Claude Opus 4.8 leads in SWE-bench software engineering benchmarks (78.4%), while Gemini 3 Flash is more budget-friendly at $3/1M per 1M output tokens. Review the complete breakdown below to determine which model best fits your performance and budget requirements.

Executive Comparison Verdict

Bottom Line: Choose Claude Opus 4.8 if your priority is peak reasoning, complex code generation, and top preference Elo. Choose Gemini 3 Flash if you are optimizing for low latency, high throughput, and cost-efficient API deployment.
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Verified Head-to-Head Advantage Breakdown

10 direct benchmark disciplines evaluated across capability, speed, and cost

Claude Opus 4.8 (5)Gemini 3 Flash (5)
Claude Opus 4.8
5 of 10 Wins
✓Preference Elo✓Coding Elo✓LiveBench✓SWE-bench✓GPQA Diamond
Gemini 3 Flash
5 of 10 Wins
✓Time to first token✓Output speed✓Input price✓Output price✓Context window
Anthropic
Leads 5 of 10 metrics
Claude Opus 4.8

Prior Opus generation still billed at $5/$25. Kept as a compare baseline against Opus 5.

Opus 4.8Elo 1,598$25/1M out
Google
Leads 5 of 10 metrics
Gemini 3 Flash

Fast Google frontier-adjacent model. Near-top official SWE-bench at a fraction of Opus price.

Flash TurboElo 1,495$3/1M out

Claude 4 Series Lineage & Sibling Variants

5 models

Currently comparing Claude Opus 4.8 vs Gemini 3 Flash. Alternative family tiers available.

Active: Claude Opus 4.8
Claude Opus 4.5$25Claude Opus 4.6$25Claude Sonnet 4.5$15Claude Haiku 4.5$5

Claude Opus 4.8 Thinking Depth & Cost Scaler

Model A

Simulate accuracy gains vs added response time & token cost

Mode: Medium (16k budget)

Reasoning models “think before answering” by generating internal reasoning tokens. Higher effort improves math, coding, and logic accuracy, but increases response delay and token costs.

Thinking Delay
330 ms
Standard speed
Reasoning Depth
~3,200
Internal tokens
Cost / 1k Calls
$90.00
9.0× standard bill
Accuracy Boost
+5.2% accuracy
STEM & SWE-bench
Top Rival Showdowns for Claude Opus 4.8
All Matchups
Compare vs:vs GPT-5vs Gemini 3 Provs Grok 4.6vs DeepSeek V4 Provs Qwen 3 Max
Preference LeaderClaude Opus 4.8 Wins

Claude Opus 4.8

Δ 103 Arena Elo pts

Throughput LeaderGemini 3 Flash Wins

Gemini 3 Flash

190 tok/s

Value per Dollar LeaderGemini 3 Flash Wins

Gemini 3 Flash

$3 / 1M output

Capability Percentiles

Relative percentile scores computed across all active models in the benchmark catalog.

Multi-Dimensional Capability Radar

Leaders Matchup Capability Radar

Comparing top Western standard models with China's leading frontier rival across 6 skill dimensions. Tap any spoke or dot to inspect.

Tap any node to inspect
Percentile 0–100
Head-to-Head Comparison

Overall Matchup Breakdown

Category wins across reasoning intelligence, generation speed, and token cost.

Claude Opus 4.8 (5)vsGemini 3 Flash (5)
Claude Opus 4.8: 5W (50%)Overall: Even matchupGemini 3 Flash: 5W (50%)
← Claude Opus 4.8Gemini 3 Flash →
🏆Claude Opus 4.8(5/5)

Intelligence & Reasoning

Preference Elo, Coding proficiency, SWE-bench & LiveBench accuracy

Benchmark
Claude Opus 4.8vsGemini 3 Flash
Preference Elo
1,598vs1,495+103
Coding Elo
1,604vs1,510+94
SWE-bench
78.4%vs75.8%+2.6%
LiveBench
73.6%vs66.8%+6.8%
GPQA Diamond
86.2%vs78.4%+7.8%
Claude Opus 4.8: 5WGemini 3 Flash: 0W
🏆Gemini 3 Flash(2/2)

Speed & Latency

Generation throughput and time to first token responsiveness

Benchmark
Claude Opus 4.8vsGemini 3 Flash
Output speed
66 tok/svs190 tok/s+124 tok/s
Time to first token
330 msvs95 ms+235 ms
Claude Opus 4.8: 0WGemini 3 Flash: 2W
🏆Gemini 3 Flash(3/3)

Pricing & Capacity

Cost per million tokens and max context window length

Benchmark
Claude Opus 4.8vsGemini 3 Flash
Output price
$25/1Mvs$3/1M+$22/1M
Input price
$5/1Mvs$0.5/1M+$4.5/1M
Context window
1Mvs1M+49k
Claude Opus 4.8: 0WGemini 3 Flash: 3W

Side-by-Side Benchmark Matrix

Preference Elo+103
Claude Opus 4.81,598
lmarena · Aug 16, 2026
Gemini 3 Flash1,495
lmarena · Aug 17, 2026
Coding Elo+94
Claude Opus 4.81,604
lmarena · Aug 16, 2026
Gemini 3 Flash1,510
lmarena · Aug 17, 2026
LiveBench+6.8%
Claude Opus 4.873.6%
livebench · Aug 16, 2026
Gemini 3 Flash66.8%
livebench · Aug 17, 2026
SWE-bench+2.6%
Claude Opus 4.878.4%
swebench · Aug 16, 2026
Gemini 3 Flash75.8%
swebench · Aug 17, 2026
GPQA Diamond+7.8%
Claude Opus 4.886.2%
seed-bootstrap · Aug 16, 2026
Gemini 3 Flash78.4%
seed-bootstrap · Aug 1, 2026
Time to first token+235 ms
Claude Opus 4.8330 ms
seed-bootstrap · Aug 16, 2026
Gemini 3 Flash95 ms
seed-bootstrap · Aug 1, 2026
Output speed+124 tok/s
Claude Opus 4.866 tok/s
seed-bootstrap · Aug 16, 2026
Gemini 3 Flash190 tok/s
seed-bootstrap · Aug 1, 2026
Input price+$4.5/1M
Claude Opus 4.8$5/1M
openrouter · Aug 17, 2026
Gemini 3 Flash$0.5/1M
openrouter · Aug 17, 2026
Output price+$22/1M
Claude Opus 4.8$25/1M
openrouter · Aug 17, 2026
Gemini 3 Flash$3/1M
openrouter · Aug 17, 2026
Context window+49k
Claude Opus 4.81M
openrouter · Aug 17, 2026
Gemini 3 Flash1M
openrouter · Aug 17, 2026
BenchmarkClaude Opus 4.8Gemini 3 FlashAdvantage Delta
Preference Elo
1,598
lmarena · Aug 16, 2026
1,495
lmarena · Aug 17, 2026
+103
Coding Elo
1,604
lmarena · Aug 16, 2026
1,510
lmarena · Aug 17, 2026
+94
LiveBench
73.6%
livebench · Aug 16, 2026
66.8%
livebench · Aug 17, 2026
+6.8%
SWE-bench
78.4%
swebench · Aug 16, 2026
75.8%
swebench · Aug 17, 2026
+2.6%
GPQA Diamond
86.2%
seed-bootstrap · Aug 16, 2026
78.4%
seed-bootstrap · Aug 1, 2026
+7.8%
Time to first token
330 ms
seed-bootstrap · Aug 16, 2026
95 ms
seed-bootstrap · Aug 1, 2026
+235 ms
Output speed
66 tok/s
seed-bootstrap · Aug 16, 2026
190 tok/s
seed-bootstrap · Aug 1, 2026
+124 tok/s
Input price
$5/1M
openrouter · Aug 17, 2026
$0.5/1M
openrouter · Aug 17, 2026
+$4.5/1M
Output price
$25/1M
openrouter · Aug 17, 2026
$3/1M
openrouter · Aug 17, 2026
+$22/1M
Context window
1M
openrouter · Aug 17, 2026
1M
openrouter · Aug 17, 2026
+49k
Interactive Simulator (USD)

Workload Cost & Savings Calculator

Simulate monthly production API costs in USD (US Dollar).

Save up to 89% with Gemini 3 Flash
Monthly Volume50M tokens/mo
Quick Presets:
Token Ratio (In vs Out)70% In / 30% Out
RAG / Search (10% out)Coding / Chat (50% out)
Claude Opus 4.8$550.00 / mo
In: $175Out: $375
Gemini 3 Flash$62.50 / mo
In: $17.5Out: $45
Estimated Cost Delta

Gemini 3 Flash is estimated to save $487.50/month ($5,850/year).

Based on 50M tokens (30% gen)

Key Selection Recommendations

  • 1
    Claude Opus 4.8:Pick Claude Opus 4.8 when repo-level coding accuracy is the constraint.
  • 2
    Gemini 3 Flash:Pick Gemini 3 Flash when you are optimizing output cost.
  • 3
    Gemini 3 Flash:Pick Gemini 3 Flash when time-to-first-token matters more than peak Elo.

Recommended Workload Routing

Repo / coding agentsClaude Opus 4.8

Higher SWE-bench (78.4%).

High-volume chatGemini 3 Flash

Lower output list price ($3/1M).

Voice / low-latency UIGemini 3 Flash

Lower TTFT (95 ms).

Long-document RAGGemini 3 Flash

Larger window (1M).

Screenshots / visionClaude Opus 4.8

Both accept images. Defaulting to the higher-Elo side (Claude Opus 4.8).

Target WorkloadRecommended PickEvaluation Rationale
Repo / coding agentsClaude Opus 4.8Higher SWE-bench (78.4%).
High-volume chatGemini 3 FlashLower output list price ($3/1M).
Voice / low-latency UIGemini 3 FlashLower TTFT (95 ms).
Long-document RAGGemini 3 FlashLarger window (1M).
Screenshots / visionClaude Opus 4.8Both accept images. Defaulting to the higher-Elo side (Claude Opus 4.8).

Related Editorial Dispatches & Benchmark Notes

View all news
launchJun 20, 2026

Keep Opus 4.8 on the board: a baseline, not a flagship

Opus 4.8 still bills $5/$25. We keep it so Opus 5 vs 4.8 is a real generation delta, not marketing.

launchMar 16, 2026

Gemini 3 Flash: near-top official SWE-bench at a fraction of Opus

March 2026 speed SKU. Still a useful cheap-coding compare even after 3.6/3.7 Flash.

Community Sentiment

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CompareLLM AI Matrix

Verified Head-to-Head Telemetry

LIVE BENCHMARK
VS
Anthropic

Claude Opus 4.8

Elo 1,598
SWE-bench78.4%
Speed (tok/s)66 tok/s
Input / 1M Tokens$5/1M
Output / 1M Tokens$25/1M
Google

Gemini 3 Flash

Elo 1,495
SWE-bench75.8%
Speed (tok/s)190 tok/s
Input / 1M Tokens$0.5/1M
Output / 1M Tokens$3/1M

Frequently Asked Questions

Which is better overall, Claude Opus 4.8 or Gemini 3 Flash?
Claude Opus 4.8 has the higher preference Elo in our latest snapshot (1,598). “Better” still depends on coding, price, and latency — see the table.
Which is better at coding, Claude Opus 4.8 or Gemini 3 Flash?
Claude Opus 4.8 leads SWE-bench at 78.4% vs 75.8%. SWE-bench is one harness, not your repo.
Which is cheaper to run in production?
Gemini 3 Flash output tokens are $3/1M versus $25/1M. Input prices and retry rates still move the real bill.
Which is faster, Claude Opus 4.8 or Gemini 3 Flash?
Gemini 3 Flash has the lower time-to-first-token (95 ms vs 330 ms). Tokens/sec is a separate column if you care about long completions.
Which has the larger context window?
Gemini 3 Flash accepts 1M tokens versus 1M.
Can I self-host either model?
Neither model is marked open-weights here. You are comparing hosted APIs.
Are these scores from CompareLLM’s own evals?
No. V1 aggregates public leaderboards (and optional first-party latency pings). Each cell names its source and date. Read /methodology.
What does preference Elo mean on this page?
Preference Elo is a crowd vote from LMArena / Arena. People see two hidden answers and pick the one they like more. The model that wins more often gets a higher Elo. That means people preferred it — not that it passed a school test. It is not SWE-bench, not accuracy, and not a number we invent. Claude Opus 4.8 and Gemini 3 Flash Elo cells are dated snapshots from the named source — we do not compute Arena ourselves.

Related news

  • launch · Jun 20, 2026

    Keep Opus 4.8 on the board: a baseline, not a flagship

  • launch · Mar 16, 2026

    Gemini 3 Flash: near-top official SWE-bench at a fraction of Opus

Similar Head-to-Head Comparisons

All Claude Opus 4.8 matchups →|All Gemini 3 Flash matchups →
Claude Opus 4.8 vs Claude Opus 4.6 (previous opus)Claude Opus 4.8 vs Claude Opus 5 (next opus)Gemini 3 Flash vs Gemini 2.5 Flash (previous gemini-flash)Gemini 3 Flash vs Gemini 3.6 Flash (next gemini-flash)Claude Fable 5 vs Claude Opus 4.8Gemini 3.6 Pro vs Claude Opus 4.8