Codestral 2508 vs gpt-oss-120b

Practical read: Codestral 2508 reads more context. gpt-oss-120b costs about a sixth as much and starts answering sooner. One API key runs both.

No card required. Start with 1 million free tokens.

Side by side:

Mistral: Codestral 2508 compared with OpenAI: gpt-oss-120b
Attribute	Codestral 2508 `mistralai/codestral-2508`	gpt-oss-120b `openai/gpt-oss-120b`
Price, 1M in + out	$1.27 Mistral, cheapest route	$0.21 Weights & Biases, cheapest route
Best for	Long documents	Low cost and speed
Input / output, 1M	$0.32 / $0.95	$0.032 / $0.18
Cached input	$0.03165/1M	$0.015825/1M to $0.1055/1M
Context window	256K 256,000 tokens	131K 131,072 tokens
First token, p50	1.1 s via Mistral	0.63 s via Telnyx
AI IQ	Unrated	IQ 98 #136 on AI IQ
Provider routes	1	24 with failover
Privacy	Varies by provider	Confidential E2EE and zero retention route
Recent route uptime range	100.00%	100.00%
Publisher	Mistral	OpenAI
Modes	chat	chat
More detail	Overview	Overview Pricing Providers

Price adds one million input and one million output tokens on the cheapest route. Prices and speed change: see the monthly reports and run a small eval before you choose a default.

Test both with your agent

Paste this into Claude Code, Cursor or any coding agent.

Compare Codestral 2508 and gpt-oss-120b in this project through TrustedRouter.

1. Read https://trustedrouter.com/docs/llms.txt
2. Point the OpenAI-compatible client at
   https://api.trustedrouter.com/v1 and read the key from
   TRUSTEDROUTER_API_KEY.
3. Run our eval prompts on mistralai/codestral-2508, then on openai/gpt-oss-120b.
4. Show me cost, latency and quality side by side before changing the default.

import os
from openai import OpenAI

client = OpenAI(
    base_url="https://api.trustedrouter.com/v1",
    api_key=os.environ["TRUSTEDROUTER_API_KEY"],
)
for model in ("mistralai/codestral-2508", "openai/gpt-oss-120b"):
    response = client.chat.completions.create(
        model=model,
        messages=[{"role": "user", "content": "What is the capital of France?"}],
    )
    print(model, response.choices[0].message.content)

for model in mistralai/codestral-2508 openai/gpt-oss-120b; do
  curl https://api.trustedrouter.com/v1/chat/completions \
    -H "Authorization: Bearer $TRUSTEDROUTER_API_KEY" \
    -H "Content-Type: application/json" \
    -d "{\"model\": \"$model\", \"messages\": [{\"role\": \"user\", \"content\": \"What is the capital of France?\"}]}"
done

Your agent will need an API key.

Questions

Which should I use, Mistral: Codestral 2508 or OpenAI: gpt-oss-120b?

Codestral 2508 has the larger context window. gpt-oss-120b has the lower published input-plus-output rate, more Credits provider routes and the lower measured p50 time to first token.

Is Mistral: Codestral 2508 or OpenAI: gpt-oss-120b cheaper?

The current cheapest TrustedRouter route is $1.266/1M for Mistral: Codestral 2508 and $0.211/1M for OpenAI: gpt-oss-120b. The comparison uses current catalog prices and updates as provider pricing changes.

Is Mistral: Codestral 2508 or OpenAI: gpt-oss-120b faster?

Current measured p50 time to first token is 1089 ms for Mistral: Codestral 2508 and 629 ms for OpenAI: gpt-oss-120b. These are routed probe measurements, not vendor-advertised speeds, and update as new samples arrive.

Can I test Mistral: Codestral 2508 and OpenAI: gpt-oss-120b with the same API?

Yes. Use the same OpenAI-compatible TrustedRouter base URL and API key, then change only the model id between mistralai/codestral-2508 and openai/gpt-oss-120b. This makes side-by-side evals possible without maintaining two provider integrations.

More comparisons

All comparisons

Try Codestral 2508 and gpt-oss-120b with one key.

TrustedRouter is useful when you know the model you want, but still need provider rollover, budget limits, usage records, and a prompt path you can verify.

No card required. Start with 1 million free tokens.