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Head-to-head comparison

GPT-5.3-Codex vs Ornith 1.5 397B

GPT-5.3-Codex (OpenAI) and Ornith 1.5 397B (Ornith Ai) compared on the ModelCap Index, API price, context window, provider availability, weight access and every public benchmark board they share. Figures are the same ones shown on the live rankings; nothing here is a hidden score.

Snapshot as of 20 August 2026

As of 20 August 2026, Ornith 1.5 397B holds the stronger ModelCap Index position (#12 vs #21); and Ornith 1.5 397B ships open weights.

Which should you choose?

Choose GPT-5.3-Codex if…

  • you want provider choice — 2 listed API providers against 0.

Choose Ornith 1.5 397B if…

  • you want the stronger overall ModelCap Index position — #12 against #21 (74.2 vs 66.4 points).
  • you want to self-host: Ornith 1.5 397B ships open weights while GPT-5.3-Codex is api only.
  • you want the more recently listed model — Ornith 1.5 397B was listed 18 August 2026, GPT-5.3-Codex 24 February 2026.

GPT-5.3-Codex vs Ornith 1.5 397B: specs, pricing and context

Specification comparison of GPT-5.3-Codex and Ornith 1.5 397B
FieldGPT-5.3-CodexOpenAIOrnith 1.5 397BOrnith Ai
ModelCap Index position#21#12
Index score66.474.2
EvidenceMeasuredEstimated
Input price / 1M tokens$1.75Unlisted
Output price / 1M tokens$14.00Unlisted
Context window400K tokens— tokens
Max output tokens128K—
API providers listed20
Weight accessAPI onlyOpen weights
Input modalitiesText, Image, FileText
First listed24 February 202618 August 2026
PublisherOpenAIOrnith Ai

Evidence: 1 public benchmark observation across 1 board · start rank interpolated from the launch card's own comparison table against resolved catalogue peers, discounted for measured cross-lab optimism. Prices are the lowest listed API offer per million tokens observed on the OpenRouter catalogue.

Benchmark scores: GPT-5.3-Codex vs Ornith 1.5 397B

Public benchmark boards where GPT-5.3-Codex or Ornith 1.5 397B has a published result
BoardGPT-5.3-CodexOrnith 1.5 397BLeads
Artificial Analysis Intelligence IndexArtificial Analysis45.5intelligence-index—Only one result

Scores are the sources' own published figures for each model's best evaluated configuration; ModelCap never re-runs a benchmark.

Want a different pairing? Open the interactive comparison tool to swap either model for any current ranked language model.

GPT-5.3-Codex vs Ornith 1.5 397B: common questions

Is GPT-5.3-Codex better than Ornith 1.5 397B?

Ornith 1.5 397B ranks higher on the ModelCap Index as of 20 August 2026: #12 against #21. That is a capability ranking built from public benchmark evidence with published uncertainty; whether it is "better" for you also depends on price, context and where you can run it.

Is GPT-5.3-Codex cheaper than Ornith 1.5 397B?

At least one of the two has no listed API price on ModelCap right now, so no price comparison is made.

Which has the bigger context window, GPT-5.3-Codex or Ornith 1.5 397B?

Both publish a 400K-token context window.

Which is better for coding, GPT-5.3-Codex or Ornith 1.5 397B?

The two models do not share a coding benchmark board on ModelCap yet, so no head-to-head coding score is published; the ModelCap Index position is the closest overall signal.

Are GPT-5.3-Codex and Ornith 1.5 397B open-weight models?

GPT-5.3-Codex: API only. Ornith 1.5 397B: Open weights. Open weights mean the checkpoint can be downloaded and self-hosted under its licence; API-only models are available solely through hosted endpoints.

Where can I run GPT-5.3-Codex and Ornith 1.5 397B?

ModelCap currently lists 2 API providers for GPT-5.3-Codex and 0 for Ornith 1.5 397B, from the OpenRouter catalogue snapshot the site serves; each model page lists the providers and their prices.

How current is this GPT-5.3-Codex vs Ornith 1.5 397B comparison?

Every figure comes from the sealed ModelCap dataset published 20 August 2026; the page re-renders within a minute of each data refresh, and the ModelCap Index positions are the same ones shown on the live rankings.

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