Introducing GPT-5.4 mini and nano — our most capable small models yet

GPT-5.4 mini and GPT-5.4 nano are now available in the API, Codex, and ChatGPT.

These models bring many of the strengths of the larger GPT-5.4 models into faster, more efficient packages that are ideal for:

  • high-volume workloads
  • coding assistants
  • subagents
  • multimodal tasks

Quick highlights for builders

GPT-5.4 mini

  • More than 2× faster than GPT-5 mini
  • Approaches full GPT-5.4 performance on SWE-Bench Pro, OSWorld-Verified, and other evals
  • 400k context window in the API
  • Great for:
    • coding
    • computer use
    • tool calling
    • real-time image reasoning

GPT-5.4 nano

  • The smallest and cheapest GPT-5.4 variant
  • Ideal for:
    • classification
    • data extraction
    • simple subagents
    • lightweight tasks

Availability & pricing

GPT-5.4 mini

  • API: $0.75 / $4.50 per 1M tokens
  • Codex: 30% of GPT-5.4 quota
  • ChatGPT: available to Free/Go users via Thinking or fallback

GPT-5.4 nano

  • API only: $0.20 / $1.25 per 1M tokens

Learn more

Full benchmarks, system cards, and more examples are in the official post:

Introducing GPT-5.4 mini and nano

If you’re building agentic coding pipelines, subagent workflows in Codex, or latency-sensitive apps, these models should unlock meaningful cost and speed wins right away.

Feel free to drop any feedback or questions on integration tips, quota details, use-case ideas, or anything else below

Excited to see what you all build with them!

10 Likes

gosh darnit, I just did a “model selection” refresh on one of my plugins an hour ago! :sweat_smile:

5 Likes

GPT-5.4-mini is great for spinning up new sub-agents.

4 Likes

Yes!

Subagents using full models can burn through credits very quickly. It is good to know there are now fast, capable options for handling supporting tasks.

3 Likes

Pricing comparison

Model In Cached Out
gpt-5.4-mini $0.75 $0.075 $4.50
gpt-5-mini $0.25 $0.025 $2.00
Price increase 200% 200% 125%
Model In Cached Out
gpt-5.4-nano $0.20 $0.020 $1.25
gpt-5-nano $0.05 $0.005 $0.40
Price increase 300% 300% 213%

Vision Pricing - Cost token multiplier

Documentation is wrong - experimentally, currently:

Model Multiplier Max Billed Image Tokens Verified
gpt-5.4-mini 1.2 1843 API
gpt-5.4-nano 1.2 1843 API
gpt-5-mini 1.2 1843 True
gpt-5-nano 1.5 2304 True

Includes the billable tokens at "high’ per image. "detail":"low" is of no effect on these “patches” AI models, which is obfuscated in documentation.

Vision docs have the wrong multiplier for gpt-5 and gpt-5.4 mini/nano - unless cost is to be stealth increased. TBD.


API call, where I capture the image-only cost, and then de-multiply it back to see if it agrees with patches formula:

model vision vision_mult chat input calculated responses input calculated
gpt-5.4-mini patch 1.2 527 433 526 432
gpt-5-mini patch 1.2 527 433 526 432
gpt-5.4-nano patch 1.2 527 433 526 432
gpt-5-nano patch 1.5 656 432 655 432

Despite being designated for “future models”, and gpt-5.4-mini/nano being in future from the original documentation, these small models disallow the larger 2500 patches vision at “high” or the “original” resolution.

Multiplier absent from documentation

Max tokens billed per image per input

Model Multiplier low/high original
gpt-5.4 1.2 3000 12000
gpt-5.3 1.2 1843 n/a
2 Likes

It seems just about every bit of documentation is wrong.

  1. The models comparison page has rounded values for token pricing that are incorrect:

    gpt-5.4-mini vs gpt-5-mini

    Bad rounding:
    $0.075 → 0.08
    $0.025 → 0.03

  2. The “patches” multiplier in documentation is all screwed up:

    What it should look like, given the currently realized costs:

Model Multiplier
gpt-5.4-mini-2026-03-17 1.2x
gpt-5.4-nano-2026-03-17 1.2x
gpt-5.4-2026-03-05 1.2x
gpt-5.3-codex 1.2x
gpt-5.2-2025-12-11 1.2x
gpt-5-mini-2025-08-07 1.2x
gpt-5-nano-2025-08-07 1.5x
o4-mini-2025-04-16 1.72x
gpt-4.1-mini-2025-04-14 1.62x
gpt-4.1-nano-2025-04-14 2.46x
codex-mini-latest 1.72x
  1. The maximum vision input size of the new GPT-5.4-mini and nano models is wrong. You can send 1600x1600 and get billed for 50x50 patches = 2500 (haven’t tested “original”).

  2. Chat Completions with gpt-5.4-mini and nano is resizing wrong or billing wrong (cheaper). Here is sending that 1600x1600px for 2500 patches/tokens:

model vision mult ChatC Ccalculated Responses Rcalculated
gpt-5.4 patch 1.2 2813 2338 3008 2500
gpt-5.4-mini patch 1.2 2813 2338 3008 2500
gpt-5.4-nano patch 1.2 2813 2338 3008 2500
gpt-5-mini patch 1.2 1834 1522 1833 1521
gpt-5-nano patch 1.5 2290 1522 2289 1521

The amount of input “usage” received back per endpoint is the columns “ChatC” and “Responses”. Image consumption then by input difference due to inclusion of the image, and then reversing the apparent multiplier.

If it were downsized, like the original mini and nano:
1248 × 1248 px (39 × 39 patches) = 1521 tokens.

This is not the only model disparity in billing between API endpoints. Here’s sending the image to others to where it should be downsized. Price should be the same between Chat Completions and Responses, but is not.

model vision vision_mult chat input calculated responses input calculated
gpt-5.3-chat-latest patch 1.2 1667 1383 1833 1521
gpt-5.3-codex patch 1.2 - - 1833 1521
gpt-5.2-chat-latest patch 1.2 1667 1383 1833 1521

And I have even another way of sending the same image to Chat Completions - the same vision, cheaper price for me still on the “chat” model:

model vision vision_mult chat input calculated r rerror
gpt-5.4 patch 1.2 2813 2338 E400 E400
gpt-5.3-chat-latest patch 1.2 1548 1284 E400 E400

Vision price inflation

Ultimately, when I integrate what the API is currently costing into my own calculator, - the same image, downsized manually to the old “high” resolution (which doesn’t happen as documented), vision still costs 3x on mini and 3.2x on nano new models.

Updated models:

2 Likes