AISub / Blog
Guides to ChatGPT, Claude, Gemini, Perplexity, and Grok subscriptions, billing, and regional prices to help you choose and manage AI subscriptions.
31 / Subscriptions and tax
How to read tax-inclusive and tax-exclusive AI subscription quotes, understand unknown tax treatment, and verify the amount charged at checkout.
Read article32 / Subscriptions and APIs
Compare ChatGPT subscriptions and the API by product surface, billing, usage limits, use cases, and account management.
Read article33 / API cost calculation
Break down AI token costs into input, cached input, output, and tool charges with formulas and a reproducible API budgeting example.
Read article34 / AI coding tool comparison
As of November 2, 2026, a comparison of Codex, Claude Code and Gemini Antigravity at the $20, $100 and $200 monthly tiers: the October 29 ChatGPT Pro Work/Codex allowance changes, Claude Ultra's removal of the 5-hour limit on October 30, the November 2 Antigravity third-party model change, and how each bills after you run out.
Read article35 / AI agent cost management
Estimate AI agent usage costs by separating tokens, tools, runtime, storage, retries, and human review with a practical budget formula.
Read article36 / Subscriptions & billing
A practical guide to comparing AI subscription prices by purchase channel, plan, billing period, tax basis, currency, exchange rate, and data freshness.
Read article37 / Subscriptions & billing
As of November 9, 2026, compare ChatGPT Pro 100, 200, and 500 by monthly price, usage relative to Plus (10x, 20x, 50x), no five-hour limit, Ultrafast, and credits, plus what changed after the Pro 200 reduction was canceled on October 29.
Read article38 / Subscriptions & billing
ChatGPT Enterprise pricing explained: token rates, seat fees, monthly workspace budgets, and differences from Plus, Pro, Business, and API billing.
Read articleWebsite prices cover ChatGPT. App Store prices cover ChatGPT, Claude, Gemini, Perplexity and Grok. Google Play is not covered. A listed price does not establish purchase eligibility.
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Claude
Gemini
Perplexity
Grok