Model Comparison 2026

GPT-5.3-Codex vs GPT-5.6 Sol

GPT-5.3-Codex
OpenAI · Balanced · Proprietary
$5.42/1M · 400K ctx
GPT-5.6 Sol
OpenAI · Frontier · Proprietary
$13/1M · 1.1M ctx

Community Vote

Pick a winner in each dimension — change your vote anytime.

Output Quality
Correctness and depth of what it produces
Agentic Ability
Tool calls, instruction-following, and multi-step tasks
Speed
Tokens per second and time-to-first-token
Value for $
How much capability you get per dollar
Reliability
Consistent results — fewer refusals, loops, and format breaks

Specs & Pricing, Side by Side

Spec
GPT-5.3-Codex
Sol
Maker
OpenAI
OpenAI
Blended price / 1M
$5.42
$13
Input / output
$1.75 in · $14 out / 1M tokens
$5.00 in · $30 out / 1M tokens
Context window
400K
1.1M
Open weights
No
No
Tool use
Yes
Yes
Reasoning
Yes
Yes
Output Quality
8.8
9.7
Agentic Ability
9.3
9.6
Speed
7.8
7.4
Value for $
7.8
7.8
Reliability
8.7
9.3

Pricing and capabilities synced from the OpenRouter catalogue. Scores are editorial (0–10).

Verdict: GPT-5.3-Codex or Sol?

Updated 2026-07-17

Choose GPT-5.3-Codex if you want codex CLI users and dedicated coding agents. Choose GPT-5.6 Sol if you want hard coding and research tasks for teams in the OpenAI ecosystem.

In our editorial scoring, GPT-5.6 Sol leads in 3 of five dimensions (output quality, agentic ability and reliability), while GPT-5.3-Codex leads in 1. On price, GPT-5.3-Codex runs about $5.42 per 1M tokens (blended) and is proprietary; GPT-5.6 Sol is about $13 and proprietary.

Where GPT-5.3-Codex falls short
  • Narrower than a general flagship outside coding
  • Mid-tier pricing
Full GPT-5.3-Codex breakdown →
Where Sol falls short
  • Very new — real-world agent track record still forming
  • Slower and pricier than Terra for routine work
Full Sol breakdown →

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