Google

Gemini 3.1 Flash-Lite

Text

Gemini 3.1 Flash-Lite; 1M context, adjustable thinking; text requests through OpenAI-compatible Chat Completions

Input $0.25 / 1M tokens | Output $1.50 / 1M tokens Gemini 3.1 Flash-Lite API reference →
Get API Key Pricing
Model health Insufficient data
runapi.ai
# Base URL
https://runapi.ai

# Endpoints
POST /v1/chat/completions
POST /v1/responses
POST /v1/messages
POST /v1beta/models/gemini-3.1-flash-lite:generateContent
POST /v1beta/models/gemini-3.1-flash-lite:streamGenerateContent

curl https://runapi.ai/v1/chat/completions \
  -H "Authorization: Bearer $RUNAPI_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "gemini-3.1-flash-lite",
  "messages": [
    {
      "role": "user",
      "content": "Analyze this codebase and suggest three performance improvements with before/after examples."
    }
  ]
}'
from openai import OpenAI

client = OpenAI(
    base_url="https://runapi.ai/v1",
    api_key="your-runapi-key"
)

response = client.chat.completions.create(
    model="gemini-3.1-flash-lite",
    messages=[{"role": "user", "content": "Analyze this codebase and suggest three performance improvements with before/after examples."}]
)
import OpenAI from "openai";

const client = new OpenAI({
  baseURL: "https://runapi.ai/v1",
  apiKey: "your-runapi-key"
});

const response = await client.chat.completions.create({
  model: "gemini-3.1-flash-lite",
  messages: [{ role: "user", content: "Analyze this codebase and suggest three performance improvements with before/after examples." }]
});
https://runapi.ai 5 endpoints
OVERVIEW

What Gemini 3.1 Flash-Lite is built for

Gemini 3.1 Flash-Lite is the low-latency, low-cost model of Google's Gemini 3 series. Google builds it for simple tasks at high volume, such as translation, classification and entity extraction, document triage, and routing requests between models. The stable gemini-3.1-flash-lite reached general availability on May 7, 2026. The context window is 1,048,576 tokens and output goes up to 65,536 tokens.

Thinking is adjustable: Google offers four thinking levels, from minimal to high, and counts thinking tokens as output. Google supports function calling and structured outputs on the model.

Google's model accepts text, image, video, audio, and PDF input. On RunAPI, gemini-3.1-flash-lite accepts text input only. Send requests through the OpenAI-compatible Chat Completions endpoint (/v1/chat/completions), OpenAI Responses, Anthropic Messages, or Gemini generateContent. Google names Gemini 3.5 Flash-Lite as the replacement, and RunAPI lists it as gemini-3.5-flash-lite.

Model ID
gemini-3.1-flash-lite
Released
May 7, 2026 (general availability)
Context window
1,048,576 tokens
Max output
65,536 tokens
Thinking
Adjustable, minimal to high
Earliest shutdown (Google)
May 7, 2027
Endpoint on RunAPI
OpenAI Chat Completions, text input
Playground

Try Gemini 3.1 Flash-Lite

Pick any model and generate in seconds.

Estimated: Input $0.25 / 1M tokens | Output $1.50 / 1M tokens

Sign in to generate with RunAPI.

Sign in to generate

Sign in to start generating with your available language models.

Get API Key Sign In
Specifications

Technical details

Provider Google
Model ID gemini-3.1-flash-lite
Modality Text
Task types Synchronous
API endpoint /v1/chat/completions
/v1/responses
/v1/messages
/v1beta/models/gemini-3.1-flash-lite:generateContent
/v1beta/models/gemini-3.1-flash-lite:streamGenerateContent
Billing unit 1K tokens
Catalog status Operational
HOW IT WORKS

Use This Model in 3 Steps

  1. Get Your Key

    Sign up for free and create an API key for gemini-3.1-flash-lite from the dashboard.

  2. Send a Request

    POST to /v1/chat/completions with the gemini-3.1-flash-lite model slug and your parameters.

  3. Get Results

    Read the completed gemini-3.1-flash-lite response directly from the endpoint.

What this model offers

Endpoint coverage

Exposes 1 public endpoint(s): chat_completion.

Usage-based billing

Metered by 1K tokens with no subscription requirement.

Gemini 3.1 Flash-Lite Pricing

Endpoint
Price
chat_completion
Input: $0.25 / 1M tokens Output: $1.50 / 1M tokens
  • Cache read: $0.03 / 1M tokens
API REFERENCE

Endpoint Specification

Endpoint
POST /v1/chat/completions
Model ID
gemini-3.1-flash-lite
Task Types
chat_completion

Request parameters

No request parameters are published for this endpoint.

USE CASES

Customer support

Answer customer questions from a private knowledge base, reducing ticket volume.

Document analysis

Draft contract summaries and flag key clauses for attorney review.

Code generation

Auto-generate unit tests, code reviews, and refactoring suggestions in CI.

Usage metrics

Trusted by developers
6
API Calls / Day
100.0%
Success Rate
1.9s
Avg Generation

Verified customer feedback is not available for this model yet.

RELATED
gemini-2.5-flash-lite by Google Input $0.10 / 1M tokens | Output $0.40 / 1M tokens gemini-3.5-flash-lite by Google Input $0.15 / 1M tokens | Output $1.25 / 1M tokens gemini-2.5-flash by Google Input $0.30 / 1M tokens | Output $2.50 / 1M tokens gemini-3-flash-preview by Google Input $0.50 / 1M tokens | Output $3.00 / 1M tokens · Input $0.30 / 1M tokens | Output $1.80 / 1M tokens
FAQ

Frequently asked questions about Gemini 3.1 Flash-Lite

Should I use Gemini 3.1 Flash-Lite or Gemini 3.5 Flash-Lite?

Google names Gemini 3.5 Flash-Lite as the replacement for 3.1 Flash-Lite. Start new projects on gemini-3.5-flash-lite, and choose gemini-3.1-flash-lite when an existing workload, prompt set, or evaluation was built on it. Both models are on RunAPI under the same API key.

How long will Gemini 3.1 Flash-Lite be available?

Google lists May 7, 2027 as the earliest shutdown date for gemini-3.1-flash-lite. The preview model was shut down in May 2026, so use the stable model ID.

Can I call Gemini 3.1 Flash-Lite with the OpenAI SDK?

Yes. Point the OpenAI SDK at https://runapi.ai/v1 with your RunAPI API key and send Chat Completions requests with model set to gemini-3.1-flash-lite. Tools use the standard OpenAI tools format.

Can I send images or audio to gemini-3.1-flash-lite on RunAPI?

Not yet. Google's model reads images, video, audio, and PDFs, but RunAPI accepts text input only for gemini-3.1-flash-lite, and requests with media parts are rejected.

How do I select gemini-3.1-flash-lite?

Pass the model ID shown in the quickstart.

What's the rate limit on this variant?

Per-key rate limits scale with your usage tier. The pricing page shows current limits. If you need higher throughput, contact support to discuss tier upgrades.

Can I switch variants later?

Yes. Variant is a parameter in the request. Switch by changing the model ID — no code changes, no re-authentication, no separate billing setup. All variants share the same API key and request shape.

Does it stream?

Where streaming is available, RunAPI streams end-to-end. LLM models support token-level streaming. Media models use async task polling or webhook callbacks for result delivery.

Where do I report quality issues?

Open an issue on the public GitHub repo or email support at [email protected]. Include the task ID and model ID so the team can investigate the specific generation.

Do I need a separate provider account?

No. Your RunAPI API key is enough to access this variant and every other model in the catalog. You do not need accounts with the underlying provider.

Building with a team?

We're here to help with enterprise setup, integrations, and technical questions.

Contact Us