GPT-3.5 Turbo vs Llama 3.1 405B Instruct
Llama 3.1 405B Instruct significantly outperforms across most benchmarks. GPT-3.5 Turbo is 1.2x cheaper per token.
OpenAI · Meta · Updated for 2026
Which is better?
GPT-3.5 Turbo outperforms in 0 benchmarks, while Llama 3.1 405B Instruct is better at 5 benchmarks (DROP, GPQA, HumanEval, MATH, MMLU). Llama 3.1 405B Instruct significantly outperforms across most benchmarks.
On price, GPT-3.5 Turbo is roughly 1.2x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Llama 3.1 405B Instruct also accepts a larger context window (128,000 input tokens), making it the stronger choice for long documents and large codebases.
Based on current benchmark, pricing, and model metadata for 2026.
Choose GPT-3.5 Turbo
- cost matters — it's about 1.2x cheaper per token
Choose Llama 3.1 405B Instruct
- you want the strongest raw capability — it leads on 5 of 5 shared benchmarks
- you process long inputs — it offers a 128,000 token context window
- you want the most recent training data — it shipped Jul 2024
- you need open weights you can self-host or fine-tune
At a glance
The differences that matter most.
Performance Benchmarks
Comparative analysis across standard metrics
GPT-3.5 Turbo outperforms in 0 benchmarks, while Llama 3.1 405B Instruct is better at 5 benchmarks (DROP, GPQA, HumanEval, MATH, MMLU).
Llama 3.1 405B Instruct significantly outperforms across most benchmarks.
Arena Performance
Playground indexes and blind preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, GPT-3.5 Turbo ($0.50/1M tokens) is 1.8x cheaper than Llama 3.1 405B Instruct ($0.89/1M tokens).
For output processing, GPT-3.5 Turbo ($1.50/1M tokens) is 1.7x more expensive than Llama 3.1 405B Instruct ($0.89/1M tokens).
In conclusion, Llama 3.1 405B Instruct is more expensive than GPT-3.5 Turbo.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
Llama 3.1 405B Instruct accepts 128,000 input tokens compared to GPT-3.5 Turbo's 16,385 tokens. Llama 3.1 405B Instruct can generate longer responses up to 128,000 tokens, while GPT-3.5 Turbo is limited to 4,096 tokens.
License
Usage and distribution terms
GPT-3.5 Turbo is licensed under a proprietary license, while Llama 3.1 405B Instruct uses Llama 3.1 Community License.
License differences may affect how you can use these models in commercial or open-source projects.
Proprietary
Closed source
Llama 3.1 Community License
Open weights
Release Timeline
When each model was launched
GPT-3.5 Turbo was released on 2023-03-21, while Llama 3.1 405B Instruct was released on 2024-07-23.
Llama 3.1 405B Instruct is 16 months newer than GPT-3.5 Turbo.
Mar 21, 2023
3.4 years ago
Jul 23, 2024
2.1 years ago
1.3yr newerKnowledge Cutoff
When training data ends
GPT-3.5 Turbo has a documented knowledge cutoff of 2021-09-30, while Llama 3.1 405B Instruct's cutoff date is not specified.
We can confirm GPT-3.5 Turbo's training data extends to 2021-09-30, but cannot make a direct comparison without Llama 3.1 405B Instruct's cutoff date.
Sep 2021
—
Provider Availability
GPT-3.5 Turbo is available from Azure, OpenAI. Llama 3.1 405B Instruct is available from Lambda, DeepInfra, Fireworks, Bedrock, Together, Hyperbolic, Google, Replicate.
GPT-3.5 Turbo
Llama 3.1 405B Instruct
Outputs Comparison
Judge for yourself.
Run your own prompts against GPT-3.5 Turbo and Llama 3.1 405B Instruct side-by-side, then vote on the output you prefer.
FAQ
Common questions about GPT-3.5 Turbo vs Llama 3.1 405B Instruct.