Vibe coding platform Replit's latest update is infuriating customers with surprise cost overruns

It's worst when going over older code, one user tells us

AI coding service Replit is in trouble again as users are protesting steep cost increases and some glitches when employing the newest version of its service.

Readers may remember Replit for deleting one of its customers’ production databases and making up data.

The company promised to move on from that mess, and on September 10 launched Agent 3, a coding helper that it says offers developers an easier way to build and test apps.

Feedback on the new service, which Replit billed as “our most advanced and autonomous Agent yet” and “3x faster and 10x more cost-effective than Computer Use models”, has been mixed, with the main complaint being that certain tasks take longer, and involve more checkpoints, so therefore cost surprisingly more.

"I think it’s just launch pricing adjustment – some tasks on new apps ran over 1hr 45 minutes and only charged $4-6 but editing pre-existing apps seems to cost most overall (I spent $1k this week alone)" one user told The Register.

This person theorized, "I think they're running a lot more under the hood with subagents which probably costs them more, but on older code where you're sort of 'editing as you go' and then having it reviewing old parts of your codebase (especially with very large files), it seems to charge a lot more than just asking for new app builds - it often calls many sub agents to review the code, plan the code, check for security, execute, then fix its issues and review thousands of lines - so it feels like $2-$4 each time it does something now on prior projects. Even asking it to reset a server and wait it charges $0.40-$0.50 on average. Interestingly, in new chats for brand new apps you can ask it to build, it doesn't do this as much. "

A Reddit megathread contains many more reports of users who say their Replit bills rose rapidly once the new service commenced.

One user wrote, "Before September 11th, with Agent 2, my expenses were reasonable and in line with the value I was getting. With Agent 3, however, in just one weekend of failed attempts the costs skyrocketed, without any concrete results.".

"I typically spent between $100-$250/mo. I blew through $70 in a night at Agent 3 launch,” another Redditor wrote, alleging the new tool also performed some questionable actions. “One prompt brute forced its way through authentication, redoing auth and hard resetting a user's password to what it wanted to perform app testing on a form," the user wrote.

"Other prompt redesigned the complete app in a new UI that it made up. I stopped immediately after that because the one prompt was $20 that ruined my UI. I'd typically go through ~10 prompts/night, so at the rate it was going, it'd be around a 20x increase in cost monthly."

Part of the problem might be with Replit's June introduction of "effort-based pricing.Previously, it would charge $0.25 for each checkpoint, and a task with multiple checkpoints would simply be tallied up one by one to arrive at a total cost. But with effort-based pricing, it now bundles complicated tasks into a single more expensive checkpoint. The next month, Replit admitted "can end up being more expensive over the lifetime of a project." But the costs didn't really seem to hit users until Agent 3.

"The effort-based pricing never ran me as much before but Agent 3 has been exceptionally high," explained the user we spoke to.

"In the last week alone it charged me $1K since the new agent dropped whereas before it was never more than $180-200 a month for the same effort. It's exceptionally fair pricing with Agent 3 if you're running a brand new app. But if you have a pre-existing app and are editing along the way, pricing seems absolutely abhorrent.”

Replit is a venture-backed startup, and may be feeling pressure to increase revenue. On the same day it launched Agent 3 the company announced $250 million in funding from investors including Prysm Capital and Google's AI Futures Fund.

"With the raise and our new AI Agent, we are positioned to supercharge customer traction to become the standard for enterprises," Replit CEO Amjad Masad said at the time, before declaring "The future is exciting with millions – if not billions – of people bringing their ideas to life with a few clicks."

But it's those purportedly few clicks that seem to be causing problems for users.

We've asked Replit for clarification of the changes to Agent 3 and pricing and will amend this story upon their response. ®