TL;DR
gpt-image-2.5-flare / sunburst / gpt-image-2 and gpt-image-2-all / gpt-image-2.5-all / the three -vip models), see GPT-image-2.5 / 2 Official vs Reverse. gpt-image-2.6-all is a new reverse line for 2.6 — not a rename of gpt-image-2.5-all; the two differ in behavior and in parameter limits.Full Comparison Table
usage.output_tokens) is authoritative. The 2.6-all per-image price follows the Model Pricing tab and your final bill.Billing Models and Cost
On APIYI, the most fundamental difference between the two routes is how usage is metered: the official models bill tokens as consumed, while 2.6-all caps cost per image. That decides which route is cheaper for a given workload.Per-image cost at 1024×1024
2K / 4K, multiple images, editing, and SVG
medium and high tiers. So:
- 1K at low or medium quality: the two routes land in the same order of magnitude, and the official route may be cheaper based on actual
usage; that said, the single 2.6 measurement (low, 824 tokens ≈ $0.025) suggests the advantage may already be marginal on 2.6, so do not carry the 2.5 numbers over as a conclusion. - 1K at
highand above, or 2K/4K at medium or high quality: 2.6-all’s flat $0.025 wins outright — high-quality 2K/4K can differ by an order of magnitude. - Edits with reference images: each 1024² reference image on the official route adds about $0.0082 of input cost and pushes the single-call cost up quickly; 2.6-all bills per image and does not stack reference-image charges.
Key Differences in Detail
1. size: any valid size + native 2K/4K vs. 1536 native + super-resolved 2K/4K
Official 2.6 follows the official size rules; all four conditions must hold at once:
- Longest edge ≤ 3840
- Both edges are multiples of 16
- Aspect ratio ≤ 3:1
- Total pixels between 655,360 and 8,294,400
auto, 1024x1024, 1536x1024, 1024x1536, 2048x2048, 2048x1152, 3840x2160, 2160x3840. 2K/4K are native pixels, not upscaled.
2.6-all splits into two tiers:
- Native tier: long edge 512–1536, and any integer is delivered exactly with no 16-multiple requirement (
1000x1000,1280x720, and1536x864all pass), aspect ratio ≤3:1 - Super-resolution tier: common sizes such as
2048x2048,2048x1152,2048x1536,1920x1080,3840x2160, and2880x2880are delivered exactly; a mismatch returns 502size_not_deliverableinstead of silently snapping to a different size. The square cap is 2880 (4096x4096returns 502), and ratios beyond 3:1 such as4096x1024return 400
512x512 are rejected; 2.6-all can produce 512x512 and 512x384. For small icons or thumbnails, 2.6-all is the more flexible choice.2. n, quality, and complexity: official tiers vs. three tiers plus multiple images
n: the official route always returns one image, so multiple images require client-side concurrency; 2.6-all supports 1–4 images, bills per image, and returns 400 fromn=5.quality: the official route exposes all six tiers (low/medium/high/xhigh/max/auto), which is the officially committed quality control; 2.6-all accepts onlyauto/medium/high(low/hdreturn 400), and the three tiers currently show no verifiable image-quality difference — do not use it to control quality, and do not expect it to control size.complexity: a parameter introduced in 2.6. The official-route docs define three official levels (low/medium/high, defaulting tohighwhen omitted), but no same-prompt A/B test on the live route has demonstrated the effect yet, so do not rely on it in production; 2.6-all does not support this parameter.
3. GIF and SVG: control vs. cost
GIFframe_count of 1 or 17 does not error but falls back to the default 9 frames / 1.8 seconds, so verify the real frame count with ffprobe.
SVG
4. Response format: b64_json vs. b64_json + URL
- Official 2.6: always returns
b64_json(raw base64, nodata:prefix) and does not acceptresponse_format— passing it returns 400. To get a URL you must persist the image to your own storage. - 2.6-all:
b64_jsonby default, or passresponse_format: "url"explicitly for a 24-hour signed link. Note that url responses may omit thesizefield; only b64 responses carry it. Regenerate after the URL expires, and re-host promptly on your side.
b64_json carries a data: prefix, so the decode logic can be shared.
5. Editing: mask, multiple images, and markup
6. Speed, timeouts, and stability
Keep official statements and measurements apart:- Official 2.6: OpenAI says generation is 50% faster overall and that
flarereaches 6 seconds atlow. That is OpenAI’s best case, not a guarantee for every request. The site has no per-tier 2.6 measurements yet; use the 2.5 same-price-tier numbers as a reference:2.5-flareat 1024² measured 10 s atlow/ 21 s athigh/ 45 s atmax, and2.5-sunburst14 / 42 / 142 s. High quality and 2K/4K are noticeably slower. - 2.6-all: typically 10–46 s (1K 10–22 s, 2K 12–24 s, 4K 15–42 s), but tail latency has measured up to 198 s, so configure clients uniformly at 600 s.
- The official route runs through OpenAI, defaults to about 100 RPM, and adjusts dynamically with overall platform concurrency; the
Defaultgroup occasionally returns 429 at peak, and switching to theimage2Enterpriseenterprise group (1.2x) can bridge the gap. - 2.6-all passed 12×2, 16×1, and 8-way concurrency at 1K in testing with no 429s; 2K/4K has not been load-tested, so start with 4–8 concurrent requests and watch tail latency. 2K/4K occasionally returns 502
size_not_deliverable; retry or switch to a supported size. - On both routes, retry 5xx and timeouts twice with exponential backoff, and back off on 429.
When to Pick Each
Pick the official gpt-image-2.6-flare / sunburst
- Fields and behavior must match OpenAI exactly: existing projects built on the official SDK or official fields migrate with zero changes
- You need all six
qualitytiers, especially the finished-asset quality ofxhigh/max - You need native 2K/4K pixels for print, fine texture, or hard detail requirements
- You need precise masks, multi-image fusion (16 images), or WebP output
- You need controllable GIF per-frame sizes, or an SVG with a named authoring model and itemized cost
- You can accept metered cost fluctuation in exchange for the official route’s stability
Pick gpt-image-2.6-all (reverse)
- Cost must be capped: flat $0.025/image, the same at 2K/4K, easy to budget
- Batch production, infographics, marketing collateral, e-commerce assets
- 2K/4K large-canvas compatibility: you want a bigger canvas without native-pixel detail
- Low-cost GIF / SVG: no
svg.modeland no text-model fee - Several images per call (1–4) or a 24-hour direct URL
- Fast iteration and the native ChatGPT look up to 1536 (with fingerprint)
Client Settings
FAQ
Can I switch between the two channels by changing only the model name?
Can I switch between the two channels by changing only the model name?
size: the official route requires 16-multiples and a total-pixel range; 2.6-all’s native tier accepts any integer, and 2K/4K is super-resolutionquality: six tiers on the official route; 2.6-all only acceptsauto/medium/highresponse_format: passing it returns 400 on the official route; 2.6-all acceptsurln: the official route returns 1 image; 2.6-all returns 1–4- GIF / SVG: different field requirements and limits
b64_json carries a data: prefix, so the decode logic can be reused.Why is 2.6-all so much cheaper? Does image quality suffer?
Why is 2.6-all so much cheaper? Does image quality suffer?
When do I have to use the official route?
When do I have to use the official route?
gpt-image-2.6-flare / sunburst when you need any of: exact parity with OpenAI’s official fields, all six quality tiers (including xhigh / max), native 2K/4K pixels, precise masks, multi-image fusion (up to 16 images), WebP output, controllable GIF per-frame size, or an SVG with a named authoring model and itemized text-model cost.When should I prefer 2.6-all?
When should I prefer 2.6-all?
2K/4K: native pixels or super-resolution?
2K/4K: native pixels or super-resolution?
Does a 2K/4K request on 2.6-all always succeed?
Does a 2K/4K request on 2.6-all always succeed?
2048x2048, 2048x1152, 2048x1536, 3840x2160, 2880x2880, and others) are delivered exactly; squares above 2880, 4:1 ratios, and some 4K transparent-background requests fail (502 size_not_deliverable or 400). Validate against the response size and the actual image dimensions, and switch size or retry on failure.Can I set the final GIF dimensions?
Can I set the final GIF dimensions?
size has no effect on GIF, only frame count and duration are guaranteed, and the final pixels are decided upstream. To fix GIF dimensions today, resize or crop the file on the client.How do I choose between the two routes for SVG?
How do I choose between the two routes for SVG?
svg.model, otherwise 400). For cheap, fewer field dependencies, and a large viewBox: pick 2.6-all (no svg.model needed, $0.025 per image).Can I use the complexity parameter?
Can I use the complexity parameter?
complexity is a planning-control parameter added upstream for 2.6. The official-route docs define three official levels, but no same-prompt A/B test on the live route has demonstrated the effect yet, so do not rely on it in production; 2.6-all does not support it. You can send it for experiments, but do not treat it as a stable quality or cost control.Can I run both channels at once for failover?
Can I run both channels at once for failover?
Default group returns 429 at peak, or switch to the official route when 2.6-all fails on content policy or size. Both routes use /v1/images/generations and /v1/images/edits, so normalize the response fields and parameters once in your business layer.Related Docs
- GPT-Image-2.6 / 2.5 / 2 Official Relay Overview - Full integration docs for the five official models
- GPT Image 2.6 New Capabilities -
complexity, SVG, GIF, markup-guided edits, and the Playground - GPT-Image-2.6-All Overview - Full parameters, sizes, and error codes for the 2.6 reverse route
- GPT-image-2.5 / 2 Official vs Reverse - The previous-generation comparison
- Output format and background incompatibilities - The official 2.6 transparent × png / jpeg / webp / gif / svg matrix
- How to choose an SVG reasoning effort - Authoring models and
svg.reasoning.effortfor official SVG - Image API Essentials & Best Practices - Timeouts, disconnects, and retries
- Model Pricing - Live prices for the two official models and 2.6-all