GPT-5.2 Codex vs Step-3.5-Flash: Specs & Benchmark Comparison

CharacteristicGPT-5.2 CodexStep-3.5-Flash
CompanyOpenAIStepFun
Release DateJanuary 13, 2026February 1, 2026
Parameters196B
MultimodalYesYes
Context (input)400K66K
Context (output)128K8K
Input Price / 1M$1.75$0.10
Output Price / 1M$14.00$0.40
Average Score0.60.8
Benchmarks
Terminal-Bench 2.00.60.4

Visual Benchmark Comparison

GPT-5.2 Codex
Step-3.5-Flash
Terminal-Bench 2.00.6 vs 0.4
0.6
0.4

Verdict

Step-3.5-Flash leads in 2 out of 4 comparison categories.

Overall Performance

Both models show comparable average scores: GPT-5.2 Codex — 0.6, Step-3.5-Flash — 0.8.

API Cost

Step-3.5-Flash is 31.5x cheaper: input $0.10/1M vs $1.75/1M tokens.

Context Window

GPT-5.2 Codex supports a larger context: 400K vs 66K tokens.

Recency

Step-3.5-Flash is newer: released 2/1/2026 vs 1/13/2026.

More About These Models

Related Comparisons

The GPT-5.2 Codex and Step-3.5-Flash comparison is updated for 2026. Data includes benchmark results, API pricing, context window size and other specifications. For more detailed information, visit the GPT-5.2 Codex or Step-3.5-Flash page. See also the complete list of AI model comparisons.