User reports 100x Anthropic API charge; public reply says form bug is being fixed
A Costa Rica developer alleges a decimal-input recharge error and automated refund refusals. A Hacker News responder who says he works at Anthropic says a fix is underway.
A decimal separator becomes a billing dispute
A developer posting as rsorto on Hacker News says an intended $5.04 Anthropic API credit recharge became a $504 base charge. The author, who describes working from Costa Rica, later reported $65.52 in local tax on top, bringing the alleged card total to $569.52.
The October 16 complaint says the recharge completed without a separate final confirmation screen, and that an automated support bot repeatedly refused a refund. Those are the user’s account of the transaction and support experience; AITrending has not accessed the billing account or independently verified the card charge.
At 20:31:51 UTC, jordn, a commenter identifying himself as an Anthropic employee, replied: “I work at Anthropic and can see that there’s a UI/form bug which didn’t account for internationalization very well.” The response says a typed 5,04 became $504, that the bug was being fixed and that support would contact the user shortly.
The accounts differ on the exact input
The complainant repeatedly says they typed 5.04, with a dot, on a localized system. The responder describes 5,04, with a comma. Another commenter says entering a comma caused the Add credits screen to display a $504 total. That corroborates a reported formatting problem, but does not reproduce the complainant’s precise checkout sequence.
The author also alleges that pressing Enter immediately bypassed validation and submitted an incorrect amount. That proposed race-condition explanation remains the author’s interpretation, rather than an established root-cause analysis from the provider.
Follow-up promised, resolution still open
The public thread now contains an acknowledgment of an internationalization form problem from someone claiming to work at Anthropic. It does not establish that a production fix has shipped, a refund has arrived or other accounts have been affected at a measured scale.
This is a dispute about paying for API credits. The sources do not show that an AI agent made the purchase or that AI-generated code caused the bug, despite jokes about that possibility in the comments. The concrete development is a user-reported recharge error followed by a public promise of engineering and support follow-up.