FLUX.2 Flex Text to Image API

blackforestlabs/flux-2-flex/text-to-image
1K/2K · 8 sizes

FLUX.2 Flex Text to Image transforms natural prompts into intricate visual compositions with micro-surface textures and Hex color control. It preserves multi-subject spatial balance while rendering natural lighting dynamics.

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OutputIdle

Generated images will appear here

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Examples

flex-text-to-image-01-output.jpg

A photorealistic mid shot of a weathered larch-wood trail signpost at a high Alpine mountain pass in late afternoon. One small square metal plate at the top of the post and three arrow-shaped boards below it, each with crisp carved, white-painted capital lettering. Each board carries only its own single line of text, and nothing is repeated anywhere else: Top square plate: "SENTIERO 443" Top arrow, pointing left: "RIFUGIO NUVOLAU 1 h 20" Middle arrow, pointing right: "PASSO GIAU 45 min" Bottom arrow, pointing left: "LAGO FEDERA 1 h 50" The wood shows deep silver-grey grain, cracks, rusted bolts and patches of orange and pale-green lichen. Behind the post, jagged dolomite peaks glow pink in alpenglow above a scree slope, and a narrow dirt path leads away with two tiny out-of-focus hikers. Low warm sun from the right, shallow depth of field on the signs, 50mm lens. Lettering sharp and correctly spelled, no other words or numbers, no logos, no watermark.

flex-text-to-image-03-output.jpg

A cinematic view from the pilot's seat of a retro-futurist research spacecraft cockpit in orbit above the night side of Earth. A curved instrument console spans the frame, built from brushed aluminium, olive-green enamel panels and chunky toggle switches with metal guards. Only four backlit amber labels appear on the console, each exactly once: on the far left panel "O2 21.4%", above a round analog gauge left of centre "COOLANT °C" with the needle at 22, directly right of the central screen "NAV LOCK", and on the far right panel "DOCK 14.2 m/s". All other switches and panels are unlabeled. The central small green monochrome screen shows a wireframe orbit trace with no text. Through the wide front window, city lights trace coastlines on the dark Earth below and a thin blue atmospheric line glows along the horizon. The pilot's gloved hands rest near a throttle lever at the bottom edge. Subtle scratches, worn paint around the switches and dust drifting in the soft cabin light. Sharp, legible labels in a clean engineering typeface, physically plausible lighting, no other text, no logos, no watermark.

FLUX.2 Flex Text to Image

FLUX.2 Flex Text to Image is Black Forest Labs high-flexibility visual synthesis model designed for intricate textures and artistic typography. Powered by the FLUX.2 architecture and a 24B Mistral-3 visual language model, it interprets complex multifaceted prompts with elevated spatial fidelity, delivering outputs up to 2K resolution starting at 18 credits ($0.090).

Why Choose FLUX.2 Flex Text to Image?

  • Granular Micro-Surface TexturesExcels at depicting fine physical nuances such as woven cloth weave, aged parchment, metallic brushed finishes, and complex organic foliage.

  • Hex Color PrecisionAdhere strictly to corporate palette guidelines by directly specifying hexadecimal color codes in prompts, eliminating unintended color drift.

  • Intricate Typography RenderingEnclose phrases in double quotes to generate precise, beautifully aligned English text directly onto artistic signs, book covers, and packaging.

  • Multi-Subject Compositional BalanceLeverage the 24B Mistral-3 VLM to resolve complex multi-character scenes, spatial depth, and realistic lighting reflections.

  • Ultra-High 2K ResolutionRender up to 4MP images across 8 aspect ratios, delivering superior edge definition and rich depth for high-end digital publishing.

Parameters

ParameterRequirementDescription
promptRequired

Detailed text prompt describing subjects, micro-textures, styling, and quoted text strings. Accepts 3 to 5,000 characters.

sizeRequired

Target aspect ratio preset. Supported values: 1:1, 4:3, 3:4, 16:9, 9:16, 3:2, 2:3, auto.

1:14:33:416:99:163:22:3auto
resolutionRequired

Output rendering resolution: 1K standard HD or 2K ultra-high resolution up to 4MP.

1K2K

How to Use

  1. Draft Prompt & Surface DetailsDetail subject geometry, micro-textures, lighting direction, Hex color values, and quote-enclosed lettering.

  2. Select Ratio & ResolutionChoose from 8 aspect ratio presets and specify 1K standard or 2K ultra-high resolution based on intended distribution.

  3. Submit Generation TaskDispatch an authorized POST request to the Flex text-to-image endpoint and capture the returned task_id.

  4. Poll for CompletionQuery the task status endpoint at periodic intervals until the status advances from running to finished.

  5. Retrieve High-Fidelity AssetDownload the generated image URL from the completed payload or receive it asynchronously via callback_url.

Pricing

Flexible pay-per-request pricing reflecting specialized high-detail rendering compute, with full automatic refund protection.

TierRateDetails
1K Standard Resolution18 credits / run · $0.090Covers high-detail rendering across all 8 aspect ratios at 1K resolution
2K Ultra-High Resolution27 credits / run · $0.135Delivers up to 4MP output with razor-sharp micro-textures and intricate fine details

Best Use Cases

  • Luxury Packaging & BrandingRender bespoke consumer packaging with embossed typography, gold leaf accents, and exact corporate Hex color codes.

  • Digital Concept Art & World-BuildingCreate sprawling fantasy landscapes, sci-fi interiors, and character concepts with complex atmospheric scattering and lighting.

  • Editorial Magazine & Book CoversGenerate visually arresting print-ready cover illustrations incorporating styled headline titles and rich textural backgrounds.

  • Architectural Material ExplorationVisualize interior concepts highlighting authentic finishes like brushed concrete, oiled walnut, and fluted glass partitions.

Pro Tips

  • Enclose Key Words in Quotes:Place exact lettering inside double quotation marks to guide letterforms and prevent spelling distortions.
  • Incorporate Hex Color Values:Include explicit hexadecimal codes (e.g., #D4AF37 for metallic gold) to achieve repeatable and strict color compliance.
  • Describe Material Tactility:FLUX.2 Flex is optimized for sensory descriptors; detail tactile surfaces like 'matte ceramic glaze' or 'raw unbleached linen'.
  • Leverage 2K for Fine Printing:Always choose 2K resolution when generating assets destined for physical print, exhibition, or high-density monitors.
  • Set Up Webhook Notifications:Provide a callback_url in production integrations to receive instant HTTP notifications once rendering finishes.

Notes

  • Prompt Length Range:The prompt field must contain between 3 and 5,000 characters and include at least one non-whitespace character.
  • Dedicated Text Generation:This endpoint accepts text prompts only; for multi-image reference workflows, please use FLUX.2 Flex Edit.
  • Asynchronous Processing Pipeline:Requests are queued asynchronously and transition from not_started to running before reaching finished.
  • Automatic Balance Refund:In the event of an unexpected timeout or service failure, reserved credits are immediately and fully restored.

Related Models

FLUX.2 Flex Text to Image API FAQ

What is the FLUX.2 Flex Text to Image API?

FLUX.2 Flex Text to Image is a specialized visual generation model developed by Black Forest Labs. It translates natural language prompts into intricate compositions up to 2K resolution, excelling in micro-surface textures, Hex color accuracy, and native English typography. Powered by a 32B flow matching architecture and a 24B Mistral-3 visual language model, it balances spatial coherence with high artistic flexibility. You can call it programmatically via the API or test prompts in the playground above.

How does FLUX.2 Flex differ from FLUX.2 Pro for text-to-image?

While FLUX.2 Pro is tailored for photorealistic fidelity, fast turnaround, and cost efficiency at 6 credits per run, FLUX.2 Flex provides enhanced creative latitude for granular micro-textures, complex artistic layouts, and bespoke tactile rendering at 18 credits per run.

Can I use Hex color codes with FLUX.2 Flex Text to Image?

Yes. FLUX.2 Flex natively recognizes standard hexadecimal color codes (such as #2B5797) within prompts, ensuring generated packaging, fabrics, and backgrounds faithfully match your defined brand color specifications.

Does FLUX.2 Flex Text to Image support native English text rendering?

Yes. By surrounding your target wording in double quotation marks (for example "SUMMIT 2026"), the model will cleanly render crisp, legible English characters onto posters, storefronts, and signage.

What are the pricing rates for FLUX.2 Flex Text to Image?

Standard 1K resolution generation costs 18 credits ($0.090) per task, and 2K ultra-high resolution costs 27 credits ($0.135) per task. There are no recurring monthly minimums or upfront licensing fees.

What aspect ratios are supported by FLUX.2 Flex Text to Image?

The size parameter accepts 8 presets: 1:1, 4:3, 3:4, 16:9, 9:16, 3:2, 2:3, and auto. You can adapt dimensions for social media verticals, wide banners, or square product displays.

What happens if a FLUX.2 Flex generation task fails?

All tasks are protected by an automatic refund policy. If a generation request encounters an error or processing timeout, the pre-deducted credits are immediately returned in full to your account.