AllocateGemini 3.5 Flash vs Claude Opus 4.8
On provider list prices, Gemini 3.5 Flash costs $1.50 per million input tokens against $5 for Claude Opus 4.8: 3.3x apart. Output is $9 against $25 (2.8x).
Gemini 3.5 Flash
Claude Opus 4.8Specifications and provider list prices from the Allocate catalog, checked 2026-07-21.
What the numbers say
Take 1,000,000 requests a month at 1,200 input and 350 output tokens each. That workload costs $4,950 a month on Gemini 3.5 Flash and $14,750 on Claude Opus 4.8 at list: a gap of $9,800, or 3.0x.
Gemini 3.5 Flash reads 1M tokens per request against 200K for Claude Opus 4.8, 5.0x the window. That decides which one can take whole documents without splitting them.
Choose Gemini 3.5 Flash for
- High-volume support and triage
- Document extraction at scale
- Vision and OCR pipelines
Choose Claude Opus 4.8 for
- Hardest reasoning problems
- High-stakes analysis
- Escalation tier for agents
Common questions
Which is cheaper, Gemini 3.5 Flash or Claude Opus 4.8?
Gemini 3.5 Flash, on this workload shape. At list prices it is $1.50/$9 per million tokens in and out against $5/$25 for Claude Opus 4.8. Billed on Allocate: $1.60/$9.63 against $5.35/$26.75.
Which has the bigger context window?
Gemini 3.5 Flash: 1,000,000 tokens (1M) against 200,000 (200K) for Claude Opus 4.8.
Can I fine-tune Gemini 3.5 Flash or Claude Opus 4.8?
No. Both are closed models served over API. If you want a model you can train and own, start from an open-weights base in the catalog.
Related comparisons
Run the numbers on your workload
Or don’t choose. On Allocate a route name is the contract: point yours at one model today, swap to the other tomorrow, and compare them on your live traffic with per-token metering.