Noometry

Model comparison

GPT-5.3 Chat vs GPT-6.1 Sol

GPT-6.1 Sol is the stronger model overall, scoring 65.6 to 42.8 on the Noometry Index.

Last verified . 12 shared benchmarks.

GPT-5.3 Chat OpenAI

42.8

Rank #109 Confirmed

GPT-6.1 Sol OpenAI

65.6

Rank #6 Confirmed

Summary

  • They share 12 benchmarks with published results for both. GPT-5.3 Chat scores higher in 0 categories and GPT-6.1 Sol in 8 categories; 7 gaps are clear of the uncertainty.
  • The widest gap is in math, where GPT-6.1 Sol leads 93.7 to 38.2.
  • GPT-6.1 Sol is cheaper at $2 / $10 per million input/output tokens, against $1.75 / $14 for GPT-5.3 Chat.
  • GPT-6.1 Sol accepts more context: 1.05M tokens versus 128K.

Side by side

GPT-5.3 ChatGPT-6.1 Sol
ProviderOpenAIOpenAI
Noometry Index42.865.6
Released2026-03-032026-09-29
WeightsProprietaryProprietary
Context window128K1.05M
Max output16K128K
Input $ / M tokens$1.75$2
Output $ / M tokens$14$10
Results tracked1834

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Category by category

Coding GPT-6.1 Sol leads

GPT-5.3 Chat: 41.4 (#124), GPT-6.1 Sol: 63.2 (#8)

BenchmarkGPT-5.3 ChatGPT-6.1 Sol
LMArena Coding14081487
DeepSWE—75.2%
FrontierCode—50.2%
LMArena WebDev—1755
SciCode—55.8%

Agentic & Tool Use Not comparable

GPT-5.3 Chat: —, GPT-6.1 Sol: 39.6 (#26)

BenchmarkGPT-5.3 ChatGPT-6.1 Sol
APEX-Agents—60%
GDP.pdf—32%

Reasoning GPT-6.1 Sol leads

GPT-5.3 Chat: 28.5 (#102), GPT-6.1 Sol: 81.9 (#2)

BenchmarkGPT-5.3 ChatGPT-6.1 Sol
LMArena Hard Prompts13991466
ARC-AGI-2—94.2%
NYT Connections (extended)—95.5%
ARC-AGI-1—98.5%
CritPt—31.7%
Chess Puzzles—61%
EBR-Bench—54.3%
Mystery Game Puzzles—80%
Epoch Capabilities Index—166.09

Math GPT-6.1 Sol leads

GPT-5.3 Chat: 38.2 (#142), GPT-6.1 Sol: 93.7 (#1)

BenchmarkGPT-5.3 ChatGPT-6.1 Sol
LMArena Math13891464
FrontierMath (Tiers 1-3)—93.7%
FrontierMath Tier 4—100%
OTIS Mock AIME 2024-2025—100%
ProofBench—99%

Knowledge GPT-6.1 Sol leads

GPT-5.3 Chat: 38.8 (#140), GPT-6.1 Sol: 71.8 (#4)

BenchmarkGPT-5.3 ChatGPT-6.1 Sol
LMArena Expert13971502
GPQA Diamond—95.4%
SimpleQA Verified—73.9%

Multimodal Not comparable

GPT-5.3 Chat: —, GPT-6.1 Sol: 52.7 (#5)

BenchmarkGPT-5.3 ChatGPT-6.1 Sol
LMArena Vision—1288
Furniture Assembly—80%

Multilingual GPT-6.1 Sol leads

GPT-5.3 Chat: 50.3 (#124), GPT-6.1 Sol: 54.3 (#46)

BenchmarkGPT-5.3 ChatGPT-6.1 Sol
LMArena Non-English13821438
LMArena Chinese14321477
LMArena Russian14001455
LMArena French1397—
LMArena German1384—
LMArena Japanese1352—
LMArena Korean1346—
LMArena Spanish1371—

Instruction Following GPT-6.1 Sol leads

GPT-5.3 Chat: 72.8 (#129), GPT-6.1 Sol: 77.0 (#29)

BenchmarkGPT-5.3 ChatGPT-6.1 Sol
LMArena Instruction Following13781468

Long Context GPT-6.1 Sol leads

GPT-5.3 Chat: 42.6 (#120), GPT-6.1 Sol: 44.9 (#54)

BenchmarkGPT-5.3 ChatGPT-6.1 Sol
LMArena Longer Query13961465

Writing & Preference Too close to call

GPT-5.3 Chat: 63.1 (#68), GPT-6.1 Sol: 63.6 (#63)

BenchmarkGPT-5.3 ChatGPT-6.1 Sol
LMArena Text13891447
LMArena Creative Writing13551432
LMArena Multi-Turn14121449
EQ-Bench Creative Writing1690—

Frequently asked questions

Is GPT-5.3 Chat better than GPT-6.1 Sol?

GPT-6.1 Sol is the stronger model overall, scoring 65.6 to 42.8 on the Noometry Index.

Which is cheaper, GPT-5.3 Chat or GPT-6.1 Sol?

GPT-6.1 Sol is cheaper. It lists at $2 per million input tokens and $10 per million output tokens; GPT-5.3 Chat lists at $1.75 and $14.

Is GPT-5.3 Chat or GPT-6.1 Sol better for coding?

GPT-6.1 Sol scores higher on coding benchmarks: 63.2 versus 41.4 in the Noometry coding category.

Which has the bigger context window?

GPT-6.1 Sol does, with 1.05M tokens against 128K.

How many benchmarks do GPT-5.3 Chat and GPT-6.1 Sol share?

12 benchmarks have published results for both models. GPT-5.3 Chat has 18 scored results on Noometry and GPT-6.1 Sol has 34.

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