Gemini 3.5 Flash — Specifications
| Developer | |
|---|---|
| Type | LLM (multimodal) |
| Modality | Text, Image, Audio, Video → Text |
| Parameters | Undisclosed |
| Context window | 1M |
| Max output | 65K |
| License | Proprietary |
| Open weights | No |
| Released | 2026 |
| Input price | $1.50 /1M |
| Output price | $9.00 /1M |
| API providers | Google AI Studio, Vertex AI |
What is Gemini 3.5 Flash?
Gemini 3.5 Flash is Google’s fast multimodal model, and an unusual case of a cheaper tier
beating the more expensive one on the benchmarks most people care about: it outperforms
Gemini 3.1 Pro on coding and agentic tasks while running roughly 4× faster and about 25%
cheaper, with the same 1M-token context. Pricing is $1.50 in / $9 out per million tokens.
When the faster, cheaper model also scores higher, the “Pro” tier stops being the default
and becomes a specialist choice. For coding assistants, agent loops and anything where a user
is waiting on a response, 3.5 Flash is the better pick on every axis at once — a rare thing
in model selection, where speed, cost and quality usually trade against each other. Reserve
3.1 Pro for workloads that specifically need its multimodal depth. The one caveat is the same
one that applies across the Gemini line: check the long-context billing terms for your tier
before building a feature that routinely sends very large prompts, because the headline rate
is not always the rate you pay above 200K tokens.
Gemini 3.5 Flash pricing: API cost per 1M tokens
| Input (per 1M tokens) | $1.50 |
|---|---|
| Output (per 1M tokens) | $9.00 |
| Output/input ratio | 6× |
| Blended (4:1 in:out) | $3.00 per 1M tokens |
What Gemini 3.5 Flash costs per month
Real monthly spend at a 4:1 input-to-output mix — the ratio a typical chat or RAG workload actually produces.
| Workload | Tokens / month | Cost / month |
|---|---|---|
| Side project | 1M in / 0.25M out | $3.75 |
| Small team | 20M in / 5M out | $75 |
| Production | 200M in / 50M out | $750 |
Run your own numbers in the AI API cost calculator.
Cheaper alternatives to Gemini 3.5 Flash
| Model | Blended $/1M | You save |
|---|---|---|
| GLM 5.2 open | $2.00 | 33% cheaper |
| DeepSeek V4-Pro open | $0.522 | 83% cheaper |
| Kimi K2.7 Code open | $0.980 | 67% cheaper |
Frequently asked questions
How much does Gemini 3.5 Flash cost per 1M tokens?
Gemini 3.5 Flash costs $1.50 per 1M input tokens and $9.00 per 1M output tokens. At a typical 4:1 input-to-output mix that blends to about $3.00 per 1M tokens.
How much does Gemini 3.5 Flash cost per month?
A small-team workload of 20M input and 5M output tokens a month costs about $75 on Gemini 3.5 Flash. A side project (1M in / 0.25M out) costs roughly $3.75.
What is a cheaper alternative to Gemini 3.5 Flash?
GLM 5.2 is the strongest cheaper option in our database at $2.00 per 1M blended — about 33% less than Gemini 3.5 Flash. It is also open-weight, so self-hosting is an option.
Can I run Gemini 3.5 Flash locally?
No. Gemini 3.5 Flash is a closed, API-only model — the weights are not released, so it cannot be self-hosted.
Why does Gemini 3.5 Flash charge more for output than input?
Output tokens are generated one at a time and cannot be batched the way a prompt can, so they cost the provider more to serve. Gemini 3.5 Flash charges 6× more for output, which is why prompt-heavy workloads are far cheaper to run than generation-heavy ones.
See every Gemini model priced side by side: Gemini API pricing.
Prices are the published list rates for the model's primary API and are reviewed as providers change them. Volume, batch and cached-input discounts are not included. Compare every model side by side in the AI models database or the LLM leaderboard.
