Sponsored byFusecodeEnterprise coding API for Claude Code, Codex, and model workflows.
LogoLMSpeed
Back to models

Model compare

GPT-4 vs GPT-5.6 Luna

The readout for GPT-4 and GPT-5.6 Luna, before the detailed comparison sheet.

Model A

GPT-4

OpenAI

Contender
vs

Model B

GPT-5.6 Luna

OpenAI

Leading

Key Takeaways

Weighted outcome: GPT-5.6 Luna. Benchmark capability categories carry 80%, while price, API performance, and availability carry 20%.

Decision read

GPT-5.6 Luna

GPT-5.6 Luna has the higher weighted result; Model A / B score 8 to 92.

Evidence depth

74 data points

Includes 4 benchmark rows, 0 audit samples, and 9 provider examples.

Selection signal

Start with GPT-5.6 Luna

The charts below split 13 high-signal samples across speed, scores, and audit health.

Change comparison

Switch either side of this report to compare another model with the same LMSpeed data pipeline.

Select a different model to open a new comparison URL.

Comparison sheet

This report only uses LMSpeed data for GPT-4 and GPT-5.6 Luna: pricing, speed aggregates, third-party benchmark scores, and shared provider samples.

Model compare
GPT-4
GPT-5.6 Luna
Overall leaderContenderLeading
Weighted overall score8.0 pts92.0 pts
Benchmark category leads0 categories3 categories
Operational advantagesFirst-token latency, Free providersCheapest input price, Average speed, Provider coverage
Context window8.2K tokens1.1M tokens
Max output4.1K tokens128K tokens
Modalities

Input

Text

Output

Text

Input

FileImageText

Output

Text
Features
Text inputText outputTool callingStructured outputsJSON mode
Text inputImage inputFile inputText outputTool callingStructured outputsJSON modeReasoning

The overall result weights benchmark capability categories at 80% and price, API speed/latency, and availability at 20%. Recent test volume does not affect the winner, and missing benchmark categories are excluded.

Model metadata

Model compare
GPT-4
GPT-5.6 Luna
DeveloperOpenAIOpenAI
ReleasedMay 2023Jul 2026
ParametersNo dataNo data
TokenizerGPTGPT
Knowledge cutoff2021-09-302026-02-16
OpenRouter IDopenai/gpt-4openai/gpt-5.6-luna
ReferencesNo dataNo data

When to choose each model

This report only uses LMSpeed data for GPT-4 and GPT-5.6 Luna: pricing, speed aggregates, third-party benchmark scores, and shared provider samples.

GPT-4

GPT-4 has these operational advantages: First-token latency, Free providers.

GPT-5.6 Luna

GPT-5.6 Luna is stronger in benchmark categories (Coding, Reasoning, Math) and operational dimensions (Cheapest input price, Average speed, Provider coverage).

Benchmark score comparison

Third-party benchmark profile synced into LMSpeed; only metrics available for both models are shown.

Category performance

Compare benchmark category scores on a 0-100 scale. Select a category to inspect the gap.

Model A coverage
3 / 8
Model B coverage
6 / 8
Shared
3 shared categories

Avg. score

GPT-4

42.3

Avg. score

GPT-5.6 Luna

56.5

Agents

GPT-5.6 Luna

GPT-4-
GPT-5.6 Luna58.3

Coding

GPT-5.6 Luna leads by 7.3

GPT-449.4
GPT-5.6 Luna56.7

Reasoning

GPT-5.6 Luna leads by 17.6

GPT-436.9
GPT-5.6 Luna54.5

Knowledge

GPT-5.6 Luna

GPT-4-
GPT-5.6 Luna56.5

Math

GPT-5.6 Luna leads by 21.7

GPT-440.7
GPT-5.6 Luna62.4

Multilingual

No data

GPT-4-
GPT-5.6 Luna-

Multimodal

GPT-5.6 Luna

GPT-4-
GPT-5.6 Luna50.3

Instruction following

No data

GPT-4-
GPT-5.6 Luna-

Professional benchmark details

Metric-level scores with benchmark source, rank depth, confidence, error, and evaluation date where available.

Pricingverified

Input price

SourceGPT-4

GPT-4

$30.00/M

Rank #177/179 · confidence 4

+$29.80/M

GPT-5.6 Luna

winner

$0.200/M

Rank #32/179 · confidence 4

Pricingverified

Blended price

SourceGPT-4

GPT-4

$37.50/M

Rank #177/179 · confidence 4

+$37.05/M

GPT-5.6 Luna

winner

$0.450/M

Rank #42/179 · confidence 4

Pricingverified

Output price

SourceGPT-4

GPT-4

$60.00/M

Rank #172/179 · confidence 4

+$58.80/M

GPT-5.6 Luna

winner

$1.20/M

Rank #48/179 · confidence 4

Reasoningverified

GPQA

SourceGPT-4

GPT-4

34.9%

Rank #204/211 · confidence 4

+56.2%

GPT-5.6 Luna

winner

91.1%

Rank #21/211 · confidence 4

API audit comparison

Latest completed audits from shared providers, with four safety and integrity score groups plus report links.

Provider
GPT-4
GPT-5.6 Luna
No completed audits are available from shared providers yet.

Provider examples

Speed aggregates and input/output pricing share each provider row for real API selection and migration cost checks.

Provider
GPT-4
GPT-5.6 Luna
AIGCBAR0 tests

GPT-4

speed / latency

N/A / N/A

input / output

No data

GPT-5.6 Luna

speed / latency

N/A / N/A

input / output

No data

AI发财网0 tests

GPT-4

speed / latency

N/A / N/A

input / output

No data

GPT-5.6 Luna

speed / latency

N/A / N/A

input / output

No data

APIMart0 tests

GPT-4

gpt-4-32k

speed / latency

N/A / N/A

input / output

$1.92/M/$7.67/M

GPT-5.6 Luna

gpt-5.6-luna

speed / latency

N/A / N/A

input / output

$0/M/$0/M

AiXiaobai API0 tests

GPT-4

speed / latency

N/A / N/A

input / output

No data

GPT-5.6 Luna

speed / latency

N/A / N/A

input / output

No data

BUZZ0 tests

GPT-4

speed / latency

N/A / N/A

input / output

No data

GPT-5.6 Luna

speed / latency

N/A / N/A

input / output

No data

兔子API

GPT-4

gpt-4

speed / latency

No data

input / output

$0/request

GPT-5.6 Luna

gpt-5.6-luna

speed / latency

No data

input / output

$0/request

Newagiai

GPT-4

gpt-4-all

speed / latency

No data

input / output

$0.011/request

GPT-5.6 Luna

gpt-5.6-luna

speed / latency

No data

input / output

$0.137/M/$0.822/M

柏拉图AI

GPT-4

gpt-4-all

speed / latency

No data

input / output

$0.011/request

GPT-5.6 Luna

gpt-5.6-luna

speed / latency

No data

input / output

$0.137/M/$0.822/M

KFCV50

GPT-4

gpt-4-all

speed / latency

No data

input / output

$0.014/request

GPT-5.6 Luna

gpt-5.6-luna

speed / latency

No data

input / output

$0.014/M/$0.082/M

FAQ

Weighted outcome: GPT-5.6 Luna. Benchmark capability categories carry 80%, while price, API performance, and availability carry 20%.

Why is this comparison indexable?
It has 6 verifiable comparison points, and both models have pricing or benchmark data.
Are missing metrics invented?
No. Metrics without LMSpeed data are omitted from this report.

Rankings are based on community-submitted tests and periodic health probes. Advisory only, not official data.