GPT-4o mini vs Grok 4.3

OpenAI · US  |  xAI · US · Updated June 2026

Quick verdict

Pick GPT-4o mini for very low cost per token for its capability tier or strong coding for a small model (87.2% humaneval). Pick Grok 4.3 for video understanding from native video input or generating pdf, pptx, and xlsx files directly. On a tight budget at scale, GPT-4o mini is the value pick.

GPT-4o mini (OpenAI) and Grok 4.3 (xAI) are two of the models people most often weigh against each other in 2026. 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. Grok 4.3 is the current xAI flagship: 1M context, native video input, file generation, and live X data, ahead of the still-unreleased Grok 5. 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

SpecGPT-4o miniGrok 4.3
ProviderOpenAI (US) xAI (US)
ReleasedJuly 18, 2024 April 30, 2026
Context window128K (~192 pages) 1M (~1,500 pages)
Price (in/out)$0.15/$0.6 per 1M tokens $1.25/$2.5 per 1M tokens
Open weight?No — API only No — API only
Modalitiestext, image text, image, video, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

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.

Video understanding from native video input

Grok 4.3

A core design strength of Grok 4.3.

Generating PDF, PPTX, and XLSX files directly

Grok 4.3

A core design strength of Grok 4.3.

Real-time questions using live X data

Grok 4.3

A core design strength of Grok 4.3.

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

Grok 4.3

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 Grok 4.3, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

Grok 4.3

Larger 1M window fits more in one prompt.

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

GPT-4o mini

It is specifically built for that.

Anyone whose priority is video understanding from native video input

Grok 4.3

That is its strongest area.

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 are real: 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.

Grok 4.3: where it fits

The current xAI flagship: 1M context, native video input, file generation, and live X data, ahead of the still-unreleased Grok 5. Released April 30, 2026 by xAI, it is built for video understanding from native video input, generating PDF, PPTX, and XLSX files directly, real-time questions using live X data, and long-context, multi-agent reasoning.

Its trade-offs: higher context pricing on requests above 200K tokens, and less independent benchmark coverage than OpenAI, Anthropic, or Google. At $1.25 in / $2.5 out per million tokens, it sits in the mid price band.

The bottom line for this matchup

GPT-4o mini and Grok 4.3 overlap enough that the right pick depends on your specific job. GPT-4o mini costs less per token; Grok 4.3 holds the larger context; and each leads in its own area — GPT-4o mini for very low cost per token for its capability tier, Grok 4.3 for video understanding from native video input. Rather than crowning one, run the same hard task through both once and let the results decide.

Want both GPT-4o mini and Grok 4.3 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 GPT-4o mini or Grok 4.3 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, GPT-4o mini leans toward very low cost per token for its capability tier while Grok 4.3 leans toward video understanding from native video input, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, GPT-4o mini or Grok 4.3?

GPT-4o mini is cheaper — $0.15/$0.6 per 1M tokens vs $1.25/$2.5 per 1M tokens, roughly 8.3× apart on input.

Which has the bigger context window?

Grok 4.3 — 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 GPT-4o mini and Grok 4.3 together?

Yes — a multi-model platform like LumiChats gives you GPT-4o mini, Grok 4.3 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, GPT-4o mini or Grok 4.3?

Grok 4.3 — released April 30, 2026, about 22 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.