Claude Sonnet 5 vs GPT-4o mini

Anthropic · US  |  OpenAI · US · Updated June 2026

Quick verdict

Pick Claude Sonnet 5 for agentic workflows that plan, use tools, and run autonomously or multi-step coding, debugging, and tool use. Pick GPT-4o mini for very low cost per token for its capability tier or strong coding for a small model (87.2% humaneval). On a tight budget at scale, GPT-4o mini is the value pick.

Claude Sonnet 5 (Anthropic) and GPT-4o mini (OpenAI) are two of the models people most often weigh against each other in 2026. Claude Sonnet 5 is anthropic's most agentic Sonnet, with near-Opus-4.8 performance at Sonnet prices; the default model on Free and Pro. GPT-4o mini is openAI's budget small multimodal model — cheap, fast text-and-vision intelligence that outscored peer small models like Gemini 1.5 Flash and Claude 3 Haiku on MMLU and HumanEval at launch. They diverge most on price and context window — each quantified below from the models' real specs.

Key differences at a glance

Side-by-side specs

SpecClaude Sonnet 5GPT-4o mini
ProviderAnthropic (US) OpenAI (US)
ReleasedJune 30, 2026 July 18, 2024
Context window1M (~1,500 pages) 128K (~192 pages)
Price (in/out)$3/$15 per 1M tokens $0.15/$0.6 per 1M tokens
Open weight?No — API only No — API only
Modalitiestext, image, code text, image
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

Agentic workflows that plan, use tools, and run autonomously

Claude Sonnet 5

A core design strength of Claude Sonnet 5.

Multi-step coding, debugging, and tool use

Claude Sonnet 5

A core design strength of Claude Sonnet 5.

Everyday professional and knowledge work

Claude Sonnet 5

A core design strength of Claude Sonnet 5.

Very low cost per token for its capability tier

GPT-4o mini

A core design strength of GPT-4o mini.

Strong coding for a small model (87.2% HumanEval)

GPT-4o mini

A core design strength of GPT-4o mini.

Leading MMLU among peer small models (82%)

GPT-4o mini

A core design strength of GPT-4o mini.

Lowest cost at scale

GPT-4o mini

At $0.15/$0.6 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Largest single-prompt input

Claude Sonnet 5

Its 1M window is about 7.8× larger, fitting roughly 1,500 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

GPT-4o mini

At $0.15/$0.6 per 1M tokens it undercuts Claude Sonnet 5, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

Claude Sonnet 5

Larger 1M window fits more in one prompt.

Anyone whose priority is agentic workflows that plan, use tools, and run autonomously

Claude Sonnet 5

It is specifically built for that.

Anyone whose priority is very low cost per token for its capability tier

GPT-4o mini

That is its strongest area.

Claude Sonnet 5: where it fits

Anthropic's most agentic Sonnet, with near-Opus-4.8 performance at Sonnet prices; the default model on Free and Pro. Released June 30, 2026 by Anthropic, it is built for agentic workflows that plan, use tools, and run autonomously, multi-step coding, debugging, and tool use, everyday professional and knowledge work, and long-document analysis and reasoning.

Its trade-offs are real: lower peak accuracy than Opus 4.8 on the hardest tasks, and an updated tokenizer that can use 1.0-1.35x more tokens for the same text. At $3 in / $15 out per million tokens, it sits in the mid price band.

GPT-4o mini: where it fits

OpenAI's budget small multimodal model — cheap, fast text-and-vision intelligence that outscored peer small models like Gemini 1.5 Flash and Claude 3 Haiku on MMLU and HumanEval at launch. Released July 18, 2024 by OpenAI, it is built for very low cost per token for its capability tier, strong coding for a small model (87.2% HumanEval), leading MMLU among peer small models (82%), and text and image (vision) understanding in the API.

Its trade-offs: only 128K context with an October 2023 knowledge cutoff, and weaker on hard reasoning and coding than frontier models. At $0.15 in / $0.6 out per million tokens, it sits in the budget price band.

The bottom line for this matchup

Claude Sonnet 5 and GPT-4o mini overlap enough that the right pick depends on your specific job. GPT-4o mini costs less per token; Claude Sonnet 5 holds the larger context; and each leads in its own area — Claude Sonnet 5 for agentic workflows that plan, use tools, and run autonomously, GPT-4o mini for very low cost per token for its capability tier. Rather than crowning one, run the same hard task through both once and let the results decide.

Want both Claude Sonnet 5 and GPT-4o mini without two subscriptions? LumiChats gives you these plus 40+ models under one ₹69/day pass (about $1/day) — draft with one, cross-check with the other.

See pricing

Frequently asked questions

Is Claude Sonnet 5 or GPT-4o mini better for coding?

Public SWE-Bench figures are not available for either model, so the honest test is your own repository — run an identical real bug through both. By design, Claude Sonnet 5 leans toward agentic workflows that plan, use tools, and run autonomously while GPT-4o mini leans toward very low cost per token for its capability tier, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Claude Sonnet 5 or GPT-4o mini?

GPT-4o mini is cheaper — $3/$15 per 1M tokens vs $0.15/$0.6 per 1M tokens, roughly 20× apart on input.

Which has the bigger context window?

Claude Sonnet 5 — 1M vs 128K, about 7.8× larger. Useful only if the model actually reasons over the full window, which not all do.

Can I use both Claude Sonnet 5 and GPT-4o mini together?

Yes — a multi-model platform like LumiChats gives you Claude Sonnet 5, GPT-4o mini and 40+ others under one ₹69/day pass (about $1/day), so you can draft with one and cross-check with the other instead of buying two subscriptions.

Which is newer, Claude Sonnet 5 or GPT-4o mini?

Claude Sonnet 5 — released June 30, 2026, about 24 months after GPT-4o mini.

Related comparisons

Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.