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 Code Fast 1 for fast, cheap agentic coding at $0.20/$1.50 or low-latency code generation and terminal tasks. On a tight budget at scale, GPT-4o mini is the value pick.
GPT-4o mini (OpenAI) and Grok Code Fast 1 (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 Code Fast 1 is xAI's speed-tier coding model at $0.20/$1.50 with a 256K window — cheap, fast agentic code over frontier quality. They diverge most on price and context window — each quantified below from the models' real specs.
Key differences
Price: GPT-4o mini is about 1.3× cheaper on input ($0.15/$0.6 per 1M tokens vs $0.2/$1.5 per 1M tokens) — modest, but it adds up at steady volume.
Context window: Grok Code Fast 1 holds 2× more — 256K (~384 pages) vs 128K (~192 pages). But effective recall usually fades long before the advertised ceiling, so the bigger number only helps if the model reasons over it.
Recency: Grok Code Fast 1 is the newer model by about 14 months (released August 28, 2025), usually meaning fresher training data and capabilities.
Specifications
Spec
GPT-4o mini
Grok Code Fast 1
Provider
OpenAI (US)
xAI (US)
Released
July 18, 2024
August 28, 2025
Context window
128K (~192 pages)
256K (~384 pages)
Price (in/out)
$0.15/$0.6 per 1M tokens
$0.2/$1.5 per 1M tokens
Open weight?
No — API only
No — API only
Modalities
text, image
text, code
SWE-Bench Verified
Not published
Not published
MRCR v2 @ 1M
Not published
Not published
Who wins what
Very low cost per token for its capability tier: GPT-4o mini — At $0.15/$0.6 per 1M tokens it undercuts Grok Code Fast 1 ($0.2/$1.5 per 1M tokens), and that gap compounds at volume.
Strong coding for a small model (87.2% HumanEval): GPT-4o mini — Grok Code Fast 1 is comparatively weak here — a speed-tier coding model, not a frontier reasoner
Leading MMLU among peer small models (82%): GPT-4o mini — 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 — and it runs cheaper at $0.15/$0.6 per 1M tokens.
Fast, cheap agentic coding at $0.20/$1.50: Grok Code Fast 1 — GPT-4o mini is comparatively weak here — weaker on hard reasoning and coding than frontier models
Low-latency code generation and terminal tasks: Grok Code Fast 1 — XAI's speed-tier coding model at $0.20/$1.50 with a 256K window — cheap, fast agentic code over frontier quality — and it carries the larger 256K context.
High-volume coding pipelines where speed beats peak quality: Grok Code Fast 1 — XAI's speed-tier coding model at $0.20/$1.50 with a 256K window — cheap, fast agentic code over frontier quality — and it is the newer of the two.
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 Code Fast 1 — Its 256K window is about 2× larger than GPT-4o mini's 128K, fitting roughly 384 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 Code Fast 1, and on millions of tokens that margin decides the monthly bill.
Someone analysing very long documents or codebases: Grok Code Fast 1 — Larger 256K 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 fast, cheap agentic coding at $0.20/$1.50: Grok Code Fast 1 — 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 Code Fast 1: where it fits
XAI's speed-tier coding model at $0.20/$1.50 with a 256K window — cheap, fast agentic code over frontier quality. Released August 28, 2025 by xAI, it is built for fast, cheap agentic coding at $0.20/$1.50, low-latency code generation and terminal tasks, high-volume coding pipelines where speed beats peak quality, and a 256K window sized for real codebases.
Its trade-offs: text and code only — no image, audio or video input, xAI did not publish a SWE-Bench Verified score, a speed-tier coding model, not a frontier reasoner, and narrow focus — built for code, not general knowledge work. At $0.2 in / $1.5 out per million tokens, it sits in the budget price band.
The bottom line for this matchup
GPT-4o mini and Grok Code Fast 1 overlap enough that the right pick depends on your specific job. GPT-4o mini costs less per token; Grok Code Fast 1 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 Code Fast 1 for fast, cheap agentic coding at $0.20/$1.50. Rather than crowning one, run the same hard task through both once and let the results decide.
Frequently asked questions
Is GPT-4o mini or Grok Code Fast 1 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 Code Fast 1 leans toward fast, cheap agentic coding at $0.20/$1.50, and that positioning usually predicts which feels better on your codebase.
Which is cheaper, GPT-4o mini or Grok Code Fast 1?
GPT-4o mini is cheaper — $0.15/$0.6 per 1M tokens vs $0.2/$1.5 per 1M tokens, roughly 1.3× apart on input.
Which has the bigger context window?
Grok Code Fast 1 — 256K vs 128K, about 2× 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 Code Fast 1 together?
Yes — a multi-model platform like LumiChats gives you GPT-4o mini, Grok Code Fast 1 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 Code Fast 1?
Grok Code Fast 1 — released August 28, 2025, about 14 months after GPT-4o mini.
GPT-4o mini vs Grok Code Fast 1
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 Code Fast 1 for fast, cheap agentic coding at $0.20/$1.50 or low-latency code generation and terminal tasks. On a tight budget at scale, GPT-4o mini is the value pick.
GPT-4o mini (OpenAI) and Grok Code Fast 1 (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 Code Fast 1 is xAI's speed-tier coding model at $0.20/$1.50 with a 256K window — cheap, fast agentic code over frontier quality. They diverge most on price and context window — each quantified below from the models' real specs.
Key differences at a glance
▸Price: GPT-4o mini is about 1.3× cheaper on input ($0.15/$0.6 per 1M tokens vs $0.2/$1.5 per 1M tokens) — modest, but it adds up at steady volume.
▸Context window: Grok Code Fast 1 holds 2× more — 256K (~384 pages) vs 128K (~192 pages). But effective recall usually fades long before the advertised ceiling, so the bigger number only helps if the model reasons over it.
▸Recency: Grok Code Fast 1 is the newer model by about 14 months (released August 28, 2025), usually meaning fresher training data and capabilities.
Side-by-side specs
Spec
GPT-4o mini
Grok Code Fast 1
Provider
OpenAI (US)
xAI (US)
Released
July 18, 2024
August 28, 2025
Context window
128K (~192 pages)
256K (~384 pages)
Price (in/out)
$0.15/$0.6 per 1M tokens
$0.2/$1.5 per 1M tokens
Open weight?
No — API only
No — API only
Modalities
text, image
text, code
SWE-Bench Verified
Not published
Not published
MRCR v2 @ 1M
Not published
Not published
Who wins what
Very low cost per token for its capability tier
GPT-4o mini
At $0.15/$0.6 per 1M tokens it undercuts Grok Code Fast 1 ($0.2/$1.5 per 1M tokens), and that gap compounds at volume.
Strong coding for a small model (87.2% HumanEval)
GPT-4o mini
Grok Code Fast 1 is comparatively weak here — a speed-tier coding model, not a frontier reasoner
Leading MMLU among peer small models (82%)
GPT-4o mini
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 — and it runs cheaper at $0.15/$0.6 per 1M tokens.
Fast, cheap agentic coding at $0.20/$1.50
Grok Code Fast 1
GPT-4o mini is comparatively weak here — weaker on hard reasoning and coding than frontier models
Low-latency code generation and terminal tasks
Grok Code Fast 1
XAI's speed-tier coding model at $0.20/$1.50 with a 256K window — cheap, fast agentic code over frontier quality — and it carries the larger 256K context.
High-volume coding pipelines where speed beats peak quality
Grok Code Fast 1
XAI's speed-tier coding model at $0.20/$1.50 with a 256K window — cheap, fast agentic code over frontier quality — and it is the newer of the two.
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 Code Fast 1
Its 256K window is about 2× larger than GPT-4o mini's 128K, fitting roughly 384 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 Code Fast 1, and on millions of tokens that margin decides the monthly bill.
Someone analysing very long documents or codebases
→ Grok Code Fast 1
Larger 256K 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 fast, cheap agentic coding at $0.20/$1.50
→ Grok Code Fast 1
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 Code Fast 1: where it fits
XAI's speed-tier coding model at $0.20/$1.50 with a 256K window — cheap, fast agentic code over frontier quality. Released August 28, 2025 by xAI, it is built for fast, cheap agentic coding at $0.20/$1.50, low-latency code generation and terminal tasks, high-volume coding pipelines where speed beats peak quality, and a 256K window sized for real codebases.
Its trade-offs: text and code only — no image, audio or video input, xAI did not publish a SWE-Bench Verified score, a speed-tier coding model, not a frontier reasoner, and narrow focus — built for code, not general knowledge work. At $0.2 in / $1.5 out per million tokens, it sits in the budget price band.
The bottom line for this matchup
GPT-4o mini and Grok Code Fast 1 overlap enough that the right pick depends on your specific job. GPT-4o mini costs less per token; Grok Code Fast 1 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 Code Fast 1 for fast, cheap agentic coding at $0.20/$1.50. Rather than crowning one, run the same hard task through both once and let the results decide.
Want both GPT-4o mini and Grok Code Fast 1 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.
Is GPT-4o mini or Grok Code Fast 1 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 Code Fast 1 leans toward fast, cheap agentic coding at $0.20/$1.50, and that positioning usually predicts which feels better on your codebase.
Which is cheaper, GPT-4o mini or Grok Code Fast 1?
GPT-4o mini is cheaper — $0.15/$0.6 per 1M tokens vs $0.2/$1.5 per 1M tokens, roughly 1.3× apart on input.
Which has the bigger context window?
Grok Code Fast 1 — 256K vs 128K, about 2× 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 Code Fast 1 together?
Yes — a multi-model platform like LumiChats gives you GPT-4o mini, Grok Code Fast 1 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 Code Fast 1?
Grok Code Fast 1 — released August 28, 2025, about 14 months after GPT-4o mini.
Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.