GPT-5.4-Cyber (OpenAI) vs Grammarly

Which one should you pick? Here's the full breakdown.

GPT-5.4-Cyber (OpenAI)

B
7.2/10

OpenAI's defensive-cybersecurity variant of GPT-5.4, launched 2026-04-16. Lowered refusal boundary for security-research tasks and native binary reverse-engineering. Access gated via Trusted Access for Cyber (TAC) program -- thousands of verified defenders, hundreds of teams, no public pricing

Our Pick

Grammarly

A
8.0/10

AI writing assistant that catches errors everywhere you type -- now with full AI rewriting

CategoryGPT-5.4-Cyber (OpenAI)Grammarly
Ease of Use5.010.0
Output Quality8.57.0
Value7.07.0
Features8.08.0
Overall7.28.0

Pricing Comparison

FeatureGPT-5.4-Cyber (OpenAI)Grammarly
Free TierNoYes
Starting PriceNot publicly disclosed$0

Which Should You Pick?

Pick GPT-5.4-Cyber (OpenAI) if...

  • Higher output quality (8.5 vs 7)

Enterprise SOC teams, established security research orgs, and vetted individual defenders who can qualify for Trusted Access for Cyber. Strongest fit if your work involves binary analysis, vulnerability research, or defensive-security tooling where standard GPT-5.4 refusals actually block the work.

Visit GPT-5.4-Cyber (OpenAI)

Pick Grammarly if...

  • Easier to use (10 vs 5)
  • Has a free tier

Non-native English speakers, professionals who write lots of emails, and anyone who wants a passive grammar net running in the background. It catches things you'd miss.

Visit Grammarly

Our Verdict

Grammarly edges out GPT-5.4-Cyber (OpenAI) with a 8.0 vs 7.2 overall score. Both are solid picks, but Grammarly has the advantage in features.