For buyers comparing ChatGPT, Claude and Gemini, the biggest differences are increasingly their prices, usage limits and ads—not their ability to handle basic questions.

The catch is that similarly priced subscriptions can meter usage very differently, and providers rarely publish comparable message counts, so the headline price alone tells you little.

The article finds OpenAI has the broadest documented consumer pricing ladder, Claude has the clearest Australian-dollar pricing, and Google’s Australian consumer-plan prices remain difficult to confirm.

Several leading plans sit around US$100 a month, including Claude Max, Gemini AI Ultra, Grok Super and a reported ChatGPT Pro tier; Perplexity Max costs US$200, while Grok Plus starts at US$8.

OpenAI sets limits by model and feature rather than offering one universal message allowance: Free includes everyday text chats subject to safeguards, while more capable models and tools have separate limits.

OpenAI rolled ads out to ChatGPT Free and Go users in Australia between 4 and 6 November and introduced Pro 500 at US$500 a month alongside Pro 200 at US$200 a month.

For Australian free users, ChatGPT offers unlimited text chats as ads roll out; Claude has a free plan with no ad programme identified in the sources, and Google Vids reportedly includes up to three free 15-second clips a month.

Claude uses five-hour usage windows, and Anthropic raised limits across several plans on 31 August 2026; users can save usage and trigger a reset, while some Team seats also face weekly caps.

Google says AI Ultra offers five times AI Pro’s usage limits, but without a published absolute prompt quota, that multiplier is hard to translate into a real-world allowance.

Grok shares a weekly usage pool across its products, with Premium listed at four times Plus usage and Super at 15 times; users can buy extra credits, but xAI does not disclose an absolute allowance.

Perplexity mainly meters searches and research features, listing Pro at US$20 a month and Max at US$200; Microsoft publishes no comparable numeric Copilot quota and says some agent features use usage-based billing.

Gemini Omni 1.2 Flash became generally available on 5 November, supports native video generation up to 15 seconds and costs US$0.07 per second for 720p video; Google says it is 30% cheaper than Omni 1.1.