compare/O3vsGemini 2.5 Flash

O3 vs Gemini 2.5 Flash

Pricing, context window, capabilities, and release date — pulled from each provider's public docs. Both are available via the same AIgateway OpenAI-compatible endpoint; flip the model string to switch.

RUN BOTH LIVE

Paste a prompt. Watch them race.

Both models stream in parallel through your own AIgateway key. Tokens, latency, and cost update as they arrive.

Sign in to runLive streaming uses your own key. It's free to sign up.
 O3
openai/o3
Gemini 2.5 Flash
google/gemini-2.5-flash
ProviderOpenAIGoogle
Familyo-series
Modalitytexttext
Context window200,000 tok1,000,000 tok
Max output100,000 tok8,192 tok
Released2026-05-222026-05-22
Input price$2.00 /1M$0.300 /1M
Output price$8.00 /1M$2.50 /1M
Cache read
Tools
Streamingyesyes
Visionyes
JSON mode
Reasoning
Prompt caching
O3
openai/o3
Full spec →

o3 is OpenAI’s general-purpose reasoning model, balancing strong analytical performance with reasonable latency and cost.

Strengths
  • General-purpose chat
  • Long context
  • Tool use
Gemini 2.5 Flash
google/gemini-2.5-flash
Full spec →

Google's fast multimodal Gemini 2.5 model with strong reasoning and a 1M token context window.

Strengths
  • General-purpose chat
  • Long context
  • Tool use
SWITCH BETWEEN THEM

One key, both models, one line different.

# pip install aigateway-py openai
# aigateway-py: sub-accounts, evals, replays, jobs, webhook verify.
# openai SDK: chat/embeddings/images/audio — drop-in compat per our SDK's own guidance.
from openai import OpenAI

client = OpenAI(
    base_url="https://api.aigateway.sh/v1",
    api_key="sk-aig-...",
)

# Try O3
client.chat.completions.create(
    model="openai/o3",
    messages=[{"role":"user","content":"hello"}],
)

# Try Gemini 2.5 Flash — same client, same key
client.chat.completions.create(
    model="google/gemini-2.5-flash",
    messages=[{"role":"user","content":"hello"}],
)
Get an AIgateway keyAdd a third model

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