The hidden limits of $20 AI coding subscriptions

The $20 subscription trap

For many developers, the promise of an AI coding assistant is to remove the heavy lifting from programming. However, a recent comparison by Tom's Guide shows that paying $20 a month does not provide unlimited access to these tools. Both OpenAI's Codex and Anthropic's Claude Code have strict limitations that can cause users to hit a wall unexpectedly.

While ChatGPT's free tier allows for unlimited chatting, the coding-specific models are much more restricted. Users who code regularly may find that their monthly allowance disappears much faster than they anticipated. This is particularly true for those who need to work on complex applications or large repositories without interruption.

The core issue is that neither company guarantees a specific number of coding tasks for the subscription price. Instead, they use a system of usage limits that vary based on the specific model chosen and the difficulty of the work. This means a user's experience can vary wildly depending on how they interact with the AI.

Transparency vs. Complexity

OpenAI currently provides more visibility into how Codex handles usage limits. They publish estimated message ranges for different models, which helps users manage their token budgets. For example, users can see that different models like GPT-6 Astra or GPT-6 Luna have vastly different expected message counts within a 5-hour window.

In contrast, Anthropic remains much more vague about how Claude Code limits are calculated. They explain that usage depends on factors like conversation length, model selection, and the complexity of the work. This makes it nearly impossible for a user to predict exactly how much coding they can get done before the system tells them to wait.

Even with OpenAI's estimates, these numbers are not guaranteed. A complex task involving multiple steps can consume significantly more usage than a simple request. Additionally, cloud tasks may use more of the allowance than standard local messages, adding another layer of unpredictability to the subscription.

Token consumption and results

The amount of tokens—the units of text processed by the AI—consumed by each tool varies significantly. A benchmark involving a Figma-to-code task showed Claude Code consuming approximately 6.2 million tokens, while Codex used only 1.5 million. This means Claude Code can be more than four times more expensive in terms of token usage for certain tasks.

However, higher token consumption does not always equate to lower value. The same benchmark noted that Claude Code produced a more thorough result than Codex. Developers must weigh the quality of the output against how quickly it exhausts their remaining usage limits for the day or week.

Data from an opt-in group of 229 developers showed that Claude Code accounted for 57% of observed tokens compared to 35% for Codex CLI. While this wasn't a controlled test of identical tasks, it highlights how different users interact with these tools. The ultimate value depends on how much useful work is completed before the limit is reached.

Shared limits and future changes

Users should be aware that their coding allowance is often shared with other features. With Claude Pro, using the chatbot for research or analyzing documents reduces the amount of usage available for Claude Code. This means a morning of heavy research can leave a developer with very little room for actual coding tasks.

OpenAI is moving toward a similar shared structure for its products. Starting in December 2026, Plus, Pro, and Business subscriptions will move toward a shared usage allowance for ChatGPT and Codex. This new system will measure consumption in tokens, though instant chat will not draw from that specific allowance.

When a user hits these limits, both companies offer ways to continue working. They provide options to purchase additional usage credits or reset the allowance for a fee. Understanding these limits helps users avoid the frustration of being cut off in the middle of a project by knowing when they might need to pay for extra credits.

Choosing the right tool

The choice between Codex and Claude Code often comes down to a preference for transparency versus results. Codex has the edge for users who want to see estimated message ranges to plan their day. This visibility helps developers manage their budgets more effectively when switching between different models.

Claude Code remains a compelling choice for those who prioritize the quality of the output. Many users find it more effective for their specific projects despite the lack of clear usage tables. It is often the preferred option for developers who need a more thorough result and are willing to manage the uncertainty of the limits.

Ultimately, the best subscription depends on the intensity of the work. For occasional bug fixes, a $20 plan may be sufficient for both tools. However, for intensive work on large repositories, users should expect to encounter limits quickly and may need to plan for additional costs or more strategic usage.