Google: Gemini 3.5 Flash API Pricing
Google: Gemini 3.5 Flash costs $1.50 per 1M input tokens and $9.00 per 1M output tokens (cache reads: $0.150). Context window: 1.0M. Prices verified 2026-10-21 · source
Alternatives to consider
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From our own daily snapshot archive — independent of provider announcements.
Intelligence measures reasoning/knowledge/coding benchmarks. A high score with a low blended price = value pick; check the value chart to see where this model lands.
Token economics
| Token type | Price | vs base input |
|---|---|---|
| Standard input | $1.50 | — |
| Cache read | $0.150 | −90% |
| Cache write (5m) | $0.083 | -94% |
| Output | $9.00 | — |
| Web search tool | $14/1k searches | — |
Prompt caching stores repeated context server-side: reads cost far less, but writes carry a one-time premium.
Higher effort = deeper thinking = more reasoning tokens billed as output.
Training data ends here — newer events require retrieval or web search.
What would Google: Gemini 3.5 Flash cost you per month?
| Workload | Requests/mo | Avg tokens (in/out) | Est. monthly cost |
|---|---|---|---|
| Light chatbot | 10,000 | 800 / 400 | $48.00 |
| Coding agent | 5,000 | 8,000 / 2,000 | $150.00 |
| RAG pipeline | 30,000 | 4,000 / 500 | $315.00 |
| Doc summarizer | 2,000 | 20,000 / 1,000 | $78.00 |
Estimates use list prices without prompt caching. Caching can cut input cost by up to 90% on repeated context.
About Google: Gemini 3.5 Flash
Gemini 3.5 Flash is Google's high-efficiency multimodal model, bringing near-Pro level coding and reasoning at Flash-tier cost and speed. It is highly optimized for coding proficiency and parallel agentic execution...
Compare Google: Gemini 3.5 Flash with
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Popular head-to-heads — see all on the comparisons index.
Frequently asked questions
How much does Google: Gemini 3.5 Flash cost?
Google: Gemini 3.5 Flash costs $1.50 per 1M input tokens and $9.00 per 1M output tokens; cached input tokens cost $0.150 per 1M. Verified 2026-10-21 — provider source.
What is the context window?
1.0M tokens, with up to 66K output tokens per response. That's roughly 1311 pages of text in a single request.
Does it support prompt caching?
Yes — cached input is $0.150/1M, about 90% cheaper than standard input. Agents and RAG workloads with repeated context benefit most.
What's a cheaper alternative?
ScaleDown: Summarize saves about 99% on a typical workload with comparable quality.
Official resources
- Google: Gemini 3.5 Flash on OpenRouter — live endpoint, pricing source of record.
- Artificial Analysis leaderboard → — independent intelligence and performance rankings.
- Gemini docs → — first-party model specifications and limits.
- LMArena leaderboard → — independent human-preference rankings.
- Shred your current bill — paste a CSV and see if switching saves money.