Does FLUX-2-klein-4b support zero data retention?

Yes. FLUX-2-klein-4b is available with zero data retention on DeepInfra through the Opper gateway.

Where is FLUX-2-klein-4b hosted?

FLUX-2-klein-4b runs on US hosting routes through the Opper gateway.

Is FLUX-2-klein-4b trained on prompts and outputs?

No. Every hosting route for FLUX-2-klein-4b is configured so customer prompts and outputs are not used to train models by default.

Is a GDPR DPA available for FLUX-2-klein-4b?

Yes. A GDPR Data Processing Agreement is available on at least one route serving FLUX-2-klein-4b. Contact hello@opper.ai to receive it.

FLUX-2-klein-4b

by Black Forest Labs

FLUX-2-klein-4b is a 4 billion parameter distilled rectified flow transformer released in January 2026, built for fast image generation and editing on consumer hardware. It uses the Qwen3 4B text encoder and achieves sub-second generation on modern hardware, fitting in roughly 13GB of VRAM and running on consumer GPUs such as the RTX 3090 and RTX 4070, with quantized FP8 and NVFP4 builds reducing memory use further. Released under the Apache 2.0 license, FLUX-2-klein-4b permits personal, scientific, and commercial use, making it the most accessible variant in the FLUX-2 family. It natively supports text-to-image generation, single-reference editing, and multi-reference composition without swapping models, and a separate undistilled 4B Base model is available for fine-tuning and LoRA training, suiting rapid iteration and interactive workflows.

Call FLUX-2-klein-4b on Opper with the OpenAI SDK. Sign up without a credit card. Get started

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Key info

Input

Output

Features

Pricing

$0.014 / megapixel

Billing

Per megapixel

US residency available
Zero data retention on pay-as-you-go
No training by default
GDPR DPA available

Pricing

Usage-based pricing, billed per megapixel, not by token.

Variant	Price
Standard	$0.014 / megapixel

Available routes

FLUX-2-klein-4b runs on 1 route through the Opper gateway. Compare residency, zero data retention and training posture at a glance, with full data-handling detail per route below.

Provider	Region	Zero data retention	Training	Price
DeepInfra	US		No	$0.014 / megapixel

Uptime and availability

FLUX-2-klein-4b runs on a single route through the Opper gateway today, so its availability is that provider's availability.

100%route uptime, last 30 days

Single route, no failover target within this model.

Name a second model in the same request and the gateway tries it on retriable errors, so a busy hour never has to reach your users. Set up a fallback chain.

Measured over the last 30 days from each provider's official status feed via StatusGator. Refreshed hourly. See uptime for every provider Opper monitors.

Data handling per route

Each route hosting FLUX-2-klein-4b has its own privacy posture, residency, and GDPR terms. Postures are maintained by Opper with a last-verification timestamp.

DeepInfra — United States🇺🇸

Zero data retention: nothing is logged, held for abuse monitoring or used for training. No training on customer data. US; unknown; DPA available.

Zero data retention: Yes. Nothing is logged, held for abuse monitoring or used for training.
Training: No training on customer data.
Logging: None
Abuse monitoring: No classifier
GDPR DPA: DPA available
Transfer mechanism: unknown

Get started

Call FLUX-2-klein-4b through the Opper gateway with one API key. Opper is drop-in compatible with the OpenAI, Anthropic and Google AI SDKs.

FLUX-2-klein-4b is a premium model on Opper. Sign up needs no credit card: you get an API key straight away and the free models work in the playground and the API. Add a card to use premium models, pay-as-you-go with no minimum.

Set it up with your agent

Copy this and paste it into a coding agent like Claude Code, Cursor or Codex and it'll wire up Opper for you.

Or call it directly

1import OpenAI from "openai";
2
3const client = new OpenAI({
4  apiKey: process.env.OPPER_API_KEY,
5  baseURL: "https://api.opper.ai/v3/compat",
6});
7
8const completion = await client.chat.completions.create({
9  model: "deepinfra/black-forest-labs/FLUX-2-klein-4b",
10  messages: [{ role: "user", content: "Hello" }],
11});
12console.log(completion.choices[0].message.content);