GPT-5 vs Claude (2026)

GPT-5 and Claude Opus sit at the frontier of large language models in 2026, but they optimize for different things. Here's how to choose for your use case — and how to run both from one ₹-native API key.

Head-to-head: cost and capability

Metric	GPT-5 (₹)	Claude Opus (₹)
Input cost	₹126/M	₹504/M
Output cost	₹1,008/M	₹2,520/M
Reasoning strength	Frontier, chain-of-thought	Best at nuance, long documents
Typical latency	Standard	Slightly slower
Context window	128K	200K

When to use GPT-5

• Math and logic-heavy tasks: GPT-5 is built for multi-step, olympiad-style reasoning.
• Budget-conscious production: ₹126 input is 4x cheaper than Opus's ₹504 — a real difference at scale.
• Speed-sensitive apps: generally the quicker of the two for interactive use.
• Mature tooling: structured outputs and function calling are well-supported.

When to use Claude Opus

• Long-context analysis: a 200K window comfortably covers full documents that GPT-5's 128K window can't.
• Nuance and safety-sensitive content: stronger, more consistent instruction-following on delicate topics.
• Creative and brand writing: often the preferred model for tone-sensitive copy and long-form content.
• Low hallucination tolerance: teams that have measured fewer factual slips from Opus on their own evals.

Integration: same code, swap the model

import anthropic

client = anthropic.Anthropic(
  base_url="https://api.unoblox.ai/v1",
  api_key="ub-gw-..."
)

# Use GPT-5
response = client.messages.create(
  model="openai/gpt-5",
  messages=[{"role": "user", "content": "Solve: 2^32 + 1 = ?"}]
)

# Or use Claude Opus
response = client.messages.create(
  model="anthropic/claude-opus",
  messages=[{"role": "user", "content": "..."}]
)

Both run on the same ₹-native infrastructure, billed on one monthly GST invoice — nothing to reconcile across two vendors.

Cost example: 10 million input + 5 million output tokens

Model	Input cost	Output cost	Total
GPT-5	₹1,260	₹5,040	₹6,300
Claude Opus	₹5,040	₹12,600	₹17,640

GPT-5 costs roughly 64% less than Opus at this volume — weigh that gap against however much better Opus performs on your specific task.

Frequently asked questions

Which model is smarter: GPT-5 or Claude Opus? For raw multi-step reasoning, GPT-5 tends to edge ahead. For nuanced understanding and long-document work, Claude Opus is usually the stronger pick. Test both on your actual workload before deciding.

Can I use GPT-5 for creative tasks? Yes, but Claude Opus is generally the stronger choice for writing, brainstorming, and long-form narrative work.

What if I switch models mid-development? No friction — the same key and endpoint serve both. Update the model parameter and redeploy.

Is Claude Opus's higher output cost worth it? Only if your task genuinely needs its nuance or 200K context — Opus costs about 2.5x GPT-5 on output tokens, so it pays off fastest on long-document or brand-sensitive work.

Do I need two separate subscriptions? No. One unoblox key gives you GPT-5, Claude Opus, and 100+ other models at ₹ prices on one invoice.

Which is better for customer support chatbots? Claude Opus for tone and safety-sensitive replies; GPT-5 for reasoning-heavy tasks like ticket triage and root-cause analysis.

Get started in rupees → https://unoblox.ai/sign-in