Are Vibe-Coded Websites Bad? An Honest Answer for Founders

A vibe-coded website is not bad by default. It is a fast way to turn an idea into something you can click, and for a prototype, a demo, or an internal tool, it is often the smartest way to start. The problem shows up later, when that same quick build quietly becomes the website your business depends on to be found, to convert visitors, and to protect customer data. That is the point where the shortcuts start charging interest.

So the honest answer is that it depends on the job. A weekend build that never meets a real user carries almost no risk. A public site running on code nobody read carries quite a lot. This guide explains what vibe coding actually is, where it genuinely works, the specific ways it fails once it becomes your real website, and how to keep the speed without inheriting the debt.

What vibe coding actually means

Andrej Karpathy, a founding member of OpenAI, coined the phrase in February 2025 to describe a way of working where you let an AI write the code and barely look at it. His own description was that he would accept every suggestion and stop reading the diffs, letting the model handle the details while he stayed with the idea. The term spread fast enough that Collins Dictionary named it the word of the year for 2025.

The tools that make this possible fall into a few groups. Natural-language app builders like Lovable, Bolt, and v0 turn a written prompt into a running web app with a live preview. AI-first editors like Cursor sit inside a codebase and rewrite across files on request. Agent tools like Claude Code and Replit take a task and work through it on their own. What they share is the move that defines vibe coding, which is accepting generated code without reading it.

This is not a fringe habit anymore. IBM reports that AI now writes close to a quarter of all merged code, so the question is no longer whether founders use these tools. The question is what happens when the output becomes the thing customers actually touch.

Where a vibe-coded site is genuinely fine

For a large set of jobs, vibe coding is the right tool and the risks barely register. Prototypes built to test an idea, throwaway landing pages for a single campaign, internal dashboards only your team will see, and early demos you build to win a conversation all qualify. If no customer money and no personal data pass through the site, shipping something rough and fast beats spending three weeks on engineering nobody asked for.

The speed is real and worth using. In Stack Overflow's 2025 developer survey, most developers said AI tools cut the time they spend on tasks, and IBM notes that AI-assisted teams now ship several times faster than they used to. For working out whether an idea is worth building at all, that speed is a genuine advantage, and reaching for these tools is the smart move rather than the risky one.

The mistake is almost never using vibe coding. The mistake is leaving the prototype in place after it stops being a prototype. A build that was perfect for proving a point becomes a liability the moment real users, real payments, or real search traffic start depending on it, and that shift usually happens without anyone deciding it should.

The trouble starts when it becomes your real website

Something changes the moment a quick build starts holding customer data, taking payments, or carrying the job of ranking in search. The same code that was fine as an experiment is now a public asset with real exposure, and the shortcuts that made it fast are the parts that work against you. The three sections below cover where that shows up, starting with the one that costs the most.

The security bill comes due

Security is where unread code does the most damage, and the research on this is now hard to wave away. OX Security found that 62 percent of applications built with AI assistance shipped with at least one critical vulnerability. A Carnegie Mellon study found that while most AI-generated code runs correctly, only about one snippet in ten passes a basic security review. Escape.tech examined more than 5,600 apps built with vibe coding tools and turned up over 2,000 vulnerabilities, more than 400 exposed secrets such as API keys and credentials, and 175 cases of leaked personal data.

The pattern behind those numbers is consistent. AI models tend to skip the unglamorous safety work that experienced engineers do by habit, so generated code often ships without protection against the common attacks. Cross-site scripting, where an attacker slips their own code into a page your visitors load, is one of the biggest gaps, and a Georgetown analysis found the great majority of AI-generated code failed to defend against it. Cross-site request forgery, where a logged-in user is tricked into an action they never intended, is another. One December 2025 study tested fifteen apps across five popular tools and found that not a single one added protection against that attack or set basic security headers.

Then there are the secrets. AI-generated code has a habit of writing API keys and passwords straight into the source, where anyone who sees the code can read them, and IBM reports that hardcoded secrets in public code jumped 34 percent in a single year. There is even a new attack class called slopsquatting, where attackers register the fake package names that AI models tend to hallucinate, so one invented import can quietly pull malicious code into your build.

None of this means AI writes bad code on purpose. The explanation is simpler than that. You cannot secure code you never read, and vibe coding is defined by not reading it. For any business that stores something a customer would care about losing, that is the entire risk in one line. The OWASP Top Ten lists the attacks this code most often misses, and it is worth knowing which of them your site is currently open to.

Search engines and AI assistants may never see your site

A vibe-coded site can look finished and still be close to invisible where it counts. Most AI builders generate a single-page app, which sends the browser a nearly empty HTML file plus a large bundle of JavaScript, and the real content only appears once that JavaScript runs. Your visitors see a normal page. A crawler often sees an empty shell with nothing to index.

Google can run JavaScript, but it does so in a delayed second pass, and Google's own documentation warns that if that rendering step fails or times out, the page can be indexed with little or no content. The wider gap is with AI assistants. A study by Vercel and MERJ found that most major AI crawlers, including the ones behind ChatGPT, Claude, and Perplexity, download JavaScript without running it, so any content that exists only after the script runs is content they never read. With more people asking an assistant for a recommendation instead of scrolling a page of results, a site the assistants cannot read is a site they cannot cite.

This part is fixable, and it is the ground our own writing keeps returning to. Getting the important content into the HTML the server sends, adding the structured data that helps engines and assistants understand a page, and shaping answers so they can be quoted all decide whether a site shows up in AI results. If that side of the work matters to you, our explainer on answer engine optimization and our guide to getting cited by ChatGPT, Perplexity, and Gemini go deeper on the how.

Slow pages that quietly lose visitors

Speed is the next thing to slip. A vibe-coded site often ships one heavy JavaScript bundle, images nobody optimized, and scripts that block the page from appearing, which is a direct hit to the Core Web Vitals that Google measures and that decide how fast a page feels to a real person. A site that takes several seconds to become usable loses visitors before they read a word, and strong content cannot rescue a page people abandon while it loads. We wrote a plain walkthrough of Core Web Vitals for founders if you want to see which numbers actually matter and why they move rankings and revenue together.

The maintenance problem nobody prices in

The cost that surprises founders most arrives months later. A vibe-coded site is usually code nobody on your team read, with no tests, little documentation, and a structure that made sense to a model in the moment but not to a human trying to change it. That is fine right up until something breaks or you need a new feature, and then you are debugging software you never understood, or paying someone else to reverse-engineer it first. Many builders also keep you inside their platform, so moving the site elsewhere means rebuilding it from scratch.

The bill for skipping the engineering does not vanish. It moves to the least convenient moment you can imagine, usually a launch week or an outage, and it grows while it waits. A site you cannot safely change is a site that slowly stops keeping up with the business it represents, and by the time that becomes obvious, the cheapest fix has often already passed.

How to keep the speed without the debt

The useful takeaway is not to avoid these tools. It is to be honest about which job you are doing. Use vibe coding freely to explore an idea, to prototype, and to put something in front of people fast, and treat that output as a sketch rather than a foundation you will build a business on.

When a build graduates into your real website, the standard has to change with it. The content that matters belongs in the HTML the server sends, so search engines and AI assistants can read it without guessing. The code needs review, tests, and documentation, so it can be secured and maintained rather than merely run once. And you should own the repository outright, with no lock-in to the tool that produced it. That combination is our default at fivetwenty.one, a senior designer and engineer building with AI where it helps and reviewing everything it produces, which is how a site ends up both fast to ship and safe to depend on. You can look at how we work and the products behind it on our work page, or start a project if you want your site built from day one to move quickly and still be found.