BRAND COMPARISON
OPTERA LABS

ChatGPT vs Grok

Two product families, side by side — subscriptions, API pricing, and which one to reach for.

The short answer

ChatGPT leads on raw capability — its strongest model, GPT-5.6 Sol, posts the higher combined coding and reasoning score in this comparison. ChatGPT is the cheaper way in: GPT-5.6 Luna blends to $0.50 per million tokens, which is what matters once you are running volume rather than evaluating. ChatGPT offers the wider context window at 1.05M tokens. Most teams end up using both — one for the hard problems, one for everything else.

OpenAI

ChatGPT

OpenAI's consumer product and the most widely used AI assistant. Strongest on multimodal breadth — voice, image generation, browsing, and agent tooling all ship in the same subscription. The API line-up spans a full frontier-to-budget ladder on one 1.05M-token context.

API models
6
Max context
1.05M
xAI

Grok

xAI's assistant, bundled with X Premium. The API's headline feature is output-token pricing well below its capability peers, which makes it unusually cheap for generation-heavy workloads.

API models
1
Max context
500K

Subscriptions

What ChatGPT and Grok charge a person per month.

ChatGPT sells a consumer subscription; Grok is used mainly through its API or bundled elsewhere, so there is no like-for-like monthly price to compare. If you want a chat product you pay for monthly, that decision is already made for you.

ChatGPT

  • ChatGPT FreeFree
  • ChatGPT Plus$20/mo
  • ChatGPT Pro$200/mo

Grok

No consumer subscription tracked.

Plan prices last verified 2026-07-21.

API pricing, tier by tier

ChatGPT and Grok line-ups matched by capability tier.

TierChatGPTGrok
FlagshipGPT-5.6 Sol$5.00 / $30.00 per 1M in / out
Mid-rangeGPT-5.6 Terra$2.00 / $12.00 per 1M in / outGrok 4.5$2.00 / $6.00 per 1M in / out
BudgetGPT-5.6 Luna$0.20 / $1.20 per 1M in / out

At 10M + 2M tokens a month — a realistic mid-size production workload — the cheapest option from ChatGPT (GPT-5.6 Luna) runs about $4.40, against roughly $32.00 for Grok's Grok 4.5. Run your own numbers on the calculator before committing: the mix of input to output tokens moves this more than the headline price does.

Which one to pick

  • For the hardest reasoning and long agentic runs: ChatGPT, specifically GPT-5.6 Sol.
  • For high-volume production where cost dominates: ChatGPT, specifically GPT-5.6 Luna at $0.50 blended per million tokens.
  • For whole-repository or long-document work: ChatGPT, with up to 1.05M tokens of context.

Model-level comparisons

The brand answer is a summary. These pages compare the specific ChatGPT and Grok models against each other with full benchmark and cost breakdowns.

Other comparisons