Anthropic Claude Opus 4.8 (1M) vs Google Gemini 3.5 Flash (1M)

Side-by-side comparison of pricing, context window, capabilities, and a real-cost sample workload.

Option A

Anthropic Claude Opus 4.8 (1M)

by Anthropic
Context: 1M
Input: $5.00 / 1M
Output: $25.00 / 1M
Released: 2026-05
Option B

Google Gemini 3.5 Flash (1M)

by Google
Context: 1M
Input: $1.50 / 1M
Output: $9.00 / 1M
Released: 2026-05

Detailed Comparison

Dimension Anthropic Claude Opus 4.8 (1M) Google Gemini 3.5 Flash (1M)
Provider Anthropic Google
Context window TieTie 1M 1M
Input price ($/1M) Winner $5.00 $1.50
Output price ($/1M) Winner $25.00 $9.00
Sample workload cost Winner
1M input + 500K output tokens
$17.50 $6.00
Released TieTie 2026-05 2026-05
Tokenizer claude-4 gemini

The verdict

On the dimensions we measured, Google Gemini 3.5 Flash (1M) wins more often - particularly on cost-effectiveness for a typical 1M+0.5M workload.

Anthropic Claude Opus 4.8 (1M) - Key features

Anthropic's most capable Opus-tier model - highly autonomous, state-of-the-art on long-horizon agentic work, knowledge work and memory, with clearer, warmer writing. 1M context at standard pricing.

  • Adaptive thinking + effort (low→max)
  • State-of-the-art long-horizon agents
  • 128K max output tokens
  • 1M token context window
  • Strong code review & debugging

Google Gemini 3.5 Flash (1M) - Key features

Google's newest fast model (Google I/O 2026), built for agentic tasks and coding - beats Gemini 3.1 Pro on coding and agentic benchmarks at a fraction of the cost.

  • Fast, low-cost agentic model
  • 1M token context window
  • Strong coding benchmarks
  • Multimodal input
  • Great price/performance

How to choose

Estimate the real cost of either model for your prompts using our Token Calculator.