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Google

Gemini 3.5 Flash

Save 70%Official

google/gemini-3.5-flash

Gemini 3.5 Flash — near-flagship intelligence at Flash speed and cost.

Get an API keyView code sample
Context window
1M
Max output
66K
Input modalities
text · image · audio · video
Output modalities
text
Capabilities
Vision · Reasoning · Tool Calling · Json Mode · Coding
RouteMux name
google/gemini-3.5-flash
Live model playground

Try Gemini 3.5 Flash here

Tune the request, see the current price ceiling, and inspect the real response without leaving this model page.

streamchat
1Configure input
0 / 20,000
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2Live result

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Gemini 3.5 Flash API pricing

Source: gemini_x0.5 · Verified 2026-06-08

InputOfficial $1.5 / M tokens
$0.45/ M tokensSave 70%
OutputOfficial $9 / M tokens
$2.7/ M tokensSave 70%

Cache read $0.045/M · Cache write —/M

Estimate cost

Estimated cost$0.0072

Limited time20% extra Credits on your first top-up — up to 200 bonus Credits

Applies to your first top-up within 72 hours of signing up. Minimum $20, once per account.

Sign up and claimNo subscription. Pay for what you use.

Key capabilities

VisionReasoningTool CallingJson ModeCoding

Interface and protocols

OpenAI Chat CompletionsStreaming

Use either ID to call this model via the API.

RouteMux namegoogle/gemini-3.5-flash

You can use these names directly in the request model field.

models/gemini-3.5-flash

Replace the ROUTEMUX_KEY placeholder with your API key. Create one →

from openai import OpenAI

client = OpenAI(
    base_url="https://api.routemux.com/v1",
    api_key="<ROUTEMUX_KEY>",
)

completion = client.chat.completions.create(
    model="google/gemini-3.5-flash",
    messages=[{"role": "user", "content": "What is the meaning of life?"}],
)
print(completion.choices[0].message.content)
base_url: https://api.routemux.com/v1

Performance (last 30 days)

Related models

Gemini 3.5 Flash FAQ

›What is Gemini 3.5 Flash?

Gemini 3.5 Flash — near-flagship intelligence at Flash speed and cost.

›How large is the context window of Gemini 3.5 Flash?

Gemini 3.5 Flash supports a context window of up to 1M tokens, with up to 66K output tokens per request.

›How much does the Gemini 3.5 Flash API cost?

Through RouteMux, Gemini 3.5 Flash costs $0.45 for input and $2.7 for output (USD per 1M tokens), below the official list price.

›How do I call Gemini 3.5 Flash via API?

Gemini 3.5 Flash is OpenAI-compatible: point your base URL at RouteMux and set the model field to google/gemini-3.5-flash — no code changes needed.

›Which input and output modalities does Gemini 3.5 Flash support?

Gemini 3.5 Flash accepts text, image, audio, video as input and produces text as output.

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