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GPT-5.5 vs GPT-5 Codex

GPT-5.5

OpenAI

93#9
vs
GPT-5 Codex

OpenAI

89#35
Signal-by-Signal Comparison
SignalGPT-5.5DeltaGPT-5 Codex
Capabilities
100
--
100
Benchmarks
93
+5
88
Pricing
70
-20
90
Context window size
96
+7
89
Recency
100
+23
77
Output Capacity
85
--
85
Overall Result
3 wins
of 6
1 wins
GPT-5.5 wins 3 of 6 signals

Score History

Score History (24 data points)
GPT-5.5GPT-5 Codex
GPT-5.5

92.7

current score

Leader

GPT-5.5

right now

GPT-5 Codex

88.7

current score

LMMarketCap.com
Interactive Price Comparison
100Kcalls/month
1,000tokens (~1,333 chars)
500tokens (~667 chars)

GPT-5.5

OpenAI

Per request$0.020000
Daily$66.67
Monthly$2000.00
Annual$24000.00

GPT-5 Codex

OpenAI

Best Value
Per request$0.006250
Daily$20.83
Monthly$625.00
Annual$7500.00

GPT-5 Codex saves you $1375.00/month

That's $16500.00/year compared to GPT-5.5 at your current usage level of 100K calls/month.

69% cheaper
Choose GPT-5 Codex for cost optimization

GPT-5.5 pricing:
Input:$5.00/M tokens
Output:$30.00/M tokens
GPT-5 Codex pricing:
Input:$1.25/M tokens
Output:$10.00/M tokens
Winner
GPT-5.5

OpenAI

93

Composite Score

GPT-5 Codex

OpenAI

89

Composite Score

Signal-by-Signal Comparison
MetricGPT-5.5GPT-5 CodexWinner
Overall Score
93
89
GPT-5.5
Rank#9#35
GPT-5.5
Quality Rank#9#35
GPT-5.5
Adoption Rank#9#35
GPT-5.5
Parameters------
Context Window1050K400K
GPT-5.5
Pricing$5.00/$30.00/M$1.25/$10.00/M--
Signal Scores
Capabilities
100
100
GPT-5.5
Benchmarks
93
88
GPT-5.5
Pricing
70
90
GPT-5 Codex
Context window size
96
89
GPT-5.5
Recency
100
77
GPT-5.5
Output Capacity
85
85
GPT-5.5
Benchmark Head-to-Head(11 benchmarks)
GPT-5.5: 4GPT-5 Codex: 1
GPT-5.5
GPT-5 Codex
Normalized 0-100%
MMLU
92.4%93%
MMLU-Pro
-84.5%
GPQA Diamond
93.6%85%
MATH-500
-92.5%
HumanEval
-96.5%
SWE-bench Verified
88.7%75%
IFEval
-92%
BBH
-90.5%
Arena Elo
14751465
LiveBench
-76%
HLE
41.4%35%
Benchmark Interpretation

Our score (0-100) is driven by benchmark performance (90%) from Arena Elo ratings, MMLU, GPQA, HumanEval, SWE-bench, and 15+ standardized evaluations. Capabilities and context window serve as tiebreakers (10%). Learn more about our methodology.

GPT-5.5Elite Tier

Scores 93/100 (rank #9), placing it in the top 97% of all 290 models tracked.

Raw Quality0/100
Cost Efficiency0/100
Speed0/100
GPT-5 CodexElite Tier

Scores 89/100 (rank #35), placing it in the top 88% of all 290 models tracked.

Raw Quality0/100
Cost Efficiency0/100
Speed0/100

With only a 4-point gap, these models are in the same performance tier. The practical difference in output quality is minimal - your choice should depend on pricing, latency requirements, and specific feature needs.

When to Use Each Model

Choose GPT-5.5 when you need:

  • Processing long documents or large codebases (1050K token context)
  • Step-by-step reasoning and chain-of-thought problem solving

Choose GPT-5 Codex when you need:

  • High-volume production workloads where API costs must be minimized
  • Step-by-step reasoning and chain-of-thought problem solving
Cost-Performance Analysis
GPT-5.5
Input cost$5.00/M tokens
Output cost$30.00/M tokens
Cost per quality point$0.378
Est. monthly (1M tokens/day)$525.00
GPT-5 CodexBest Value
Input cost$1.25/M tokens
Output cost$10.00/M tokens
Cost per quality point$0.127
Est. monthly (1M tokens/day)$168.75

GPT-5 Codex offers 68% better value per quality point. At 1M tokens/day, you'd spend $168.75/month with GPT-5 Codex vs $525.00/month with GPT-5.5 - a $356.25 monthly difference.

Latency & Speed
GPT-5.5Faster
Speed score0/100
GPT-5 Codex
Speed score0/100

Both models have comparable response speeds. For most applications, the latency difference is negligible.

When latency matters most: Interactive chatbots, IDE code completion, real-time translation, and user-facing applications where response time directly impacts experience. For batch processing, background summarization, or offline analysis, latency is less critical.

Example Use Cases

Code generation & review

Based on overall model capabilities and architecture for coding tasks like generating functions, debugging, and refactoring

GPT-5.5

Customer support chatbot

Suitable for user-facing chat with competitive response times. GPT-5 Codex also offers lower per-token costs for high-volume support

GPT-5.5

Long document analysis

Larger context window (1050K tokens) can process longer documents, contracts, and research papers in a single pass

GPT-5.5

Batch data extraction

Lower output pricing ($10.00/M) reduces costs when processing thousands of records daily

GPT-5 Codex

Creative writing & content

Higher overall composite score (93/100) correlates with better nuance, coherence, and style in long-form content

GPT-5.5

Image understanding & OCR

Supports vision input - can analyze screenshots, diagrams, photos, and scanned documents directly

GPT-5.5
Which Should You Choose?
Our recommendation:
GPT-5.5

GPT-5.5 has a moderate advantage with a 4-point lead in composite score. It wins on more signal dimensions, but GPT-5 Codex has specific strengths that could make it the better choice for certain workflows.

GPT-5.5
Recommended

by OpenAI

  • Choose for Quality - Marginally better benchmark scores; both are excellent
  • Choose for Reliability - Higher uptime and faster response speeds
  • Choose for Prototyping - Stronger community support and better developer experience
  • Choose for Production - Wider enterprise adoption and proven at scale

by OpenAI

  • Choose for Cost - 68% lower pricing; better value at scale
Capability Comparison
CapabilityGPT-5.5GPT-5 Codex
Vision (Image Input)
Function Calling
Streaming
JSON Mode
Reasoning
Web Search
Image Output
Monthly Cost Calculator
1,000tokens (600 in / 400 out)
100requests/day (3,000/month)

GPT-5.5

OpenAI

$45.00
estimated monthly cost

GPT-5 Codex

OpenAI

Best Value
$14.25
estimated monthly cost

GPT-5 Codex saves you $30.75/month

That's 68% cheaper than GPT-5.5 at 1,000 tokens/request and 100 requests/day.

Assumes 60% input / 40% output token ratio per request. Actual costs may vary based on your usage pattern.

Parameters & Context
ParameterGPT-5.5GPT-5 Codex
Context Window1.1M400K
Max Output Tokens128,000128,000
Open SourceNoNo
CreatedApr 24, 2026Sep 23, 2025
Last updated: 54m ago

相关对比

GPT-5.5 vs GPT-5 Codex (2026) | LM Market Cap