# Website vs Web App: Why a Web App Is Database-Backed > A website you read. A web app is a database-backed application you use. Why the difference matters now that AI writes the code for business systems. Source: https://llamapress.ai/website-vs-web-app-the-difference-that-matters-when-your-business-runs-on-excel | Updated: 2026-10-29 --- [LlamaPress Blog](https://llamapress.ai/blog) A website you read. A web app is a database-backed application you use. Why the difference matters now that AI writes the code for business systems. [Back to all articles](https://llamapress.ai/blog) ![Kody Kendall](https://llamapress-ai-image-uploads.s3.us-west-2.amazonaws.com/jujc1ep8nuqrdiftdfer1ngp833u) Written by Kody Kendall AI & Software Engineer | Creator of the Leonardo Coding Agent Updated October 2026 A website is something you read. A web app is something you use. Both open in a browser, so most people use the two words the same way. The difference is the data underneath. A website stores a little and mostly stays the same. A web app is a database-backed application. It is built on a deep database, knows who you are, and does real work with your information. Now that people build software by asking AI to write it, knowing that difference is how you understand what the AI is building for you. In short - A website is mostly static: articles, pictures, a contact form, maybe comments. A WordPress blog is the classic example. - A web app is a database-backed application: logins, private data per user, deep search, and custom logic. YouTube, Gmail and your CRM are web apps. - A web app costs more to build because the logins, the data and the logic all have to be designed. - If your business runs on a shared spreadsheet, what you are missing is usually a web app. - AI now writes the code for custom business systems. Knowing how a database-backed app fits together lets you direct it, check it and own it. I explain this difference to business owners almost every week. Most of them know Excel far better than I do. They have run their pricing, their jobs or their orders in a spreadsheet for years. They have heard the word "database" plenty of times. But every database they have touched came through an IT person, so they have never seen what one does from the inside. The website versus web app question is the easiest door into that gap. ![A person working on a laptop in a browser, where both websites and web apps run](https://images.unsplash.com/photo-1544006659-f0b21884ce1d?crop=entropy&cs=tinysrgb&fit=max&fm=jpg&ixid=M3w4NTU2MDF8MHwxfHNlYXJjaHwxfHxwZXJzb24lMjBjb21wYXJpbmclMjB3ZWJzaXRlJTIwYW5kJTIwYXBwJTIwb24lMjBsYXB0b3B8ZW58MHx8fHwxNzkzMjkwNDA0fDA&ixlib=rb-4.1.0&q=80&w=1080) Photo by [Štefan Štefančík](https://unsplash.com/@cikstefan?utm_source=leonardo_rails_app&utm_medium=referral) on [Unsplash](https://unsplash.com/photos/person-wearing-long-sleeve-top-working-on-laptop-5p_7M5MP2Iw?utm_source=leonardo_rails_app&utm_medium=referral) ## What is a website? A website is a set of pages you read. Think of a blog, a restaurant menu, or a company's "About us" page. You write an article once, and it looks the same to every visitor. A website still has a database behind it, so it is not frozen. A WordPress blog stores its posts, its pictures and the comments people leave. But the database is shallow. It holds a small amount of content and very little custom logic. Nobody signs in to see their own version of the page. ## What is a web app? A database-backed application A web app is software that runs in your browser. You do not just read it. You use it to get work done, and it changes based on who you are and what you do. The best short name for it is a **database-backed application**: the database is the center, and every screen is a way to read or change it. Here is what a web app has that a website usually does not: - **User profiles.** People sign in, and each person sees their own data, kept separate from everyone else's. - **A much larger database.** Thousands or millions of records, connected to each other. - **Deep search.** You can find one job, one customer or one invoice across years of history in a second. - **Custom logic.** Rules that run on their own: a price that recalculates, a status that changes, an alert that fires. - **Algorithms.** YouTube recommends the next video from what you watched. Facebook suggests people you may know. Both are logic running on a database. - **Many more users.** A whole team, or a whole customer base, working in the same system at the same time. ## What "database-backed" really means A database is a set of tables, like the tabs in a workbook. Each table holds one kind of thing: customers, jobs, invoices. Each row is one record. The tables link to each other, so a job knows its customer and an invoice knows its job. "Database-backed" means the application stores everything in those tables, and the screens sit on top of them. Three things follow from that: - **One source of truth.** Everyone reads and writes the same records. There is no "which copy is current?" - **Rules live with the data.** A required field, a price formula, or an approval step is enforced every time, for every user. - **History you can trust.** You can see who changed a record and when. That matters when a number has to survive an audit. A website can have a database too, but it is not built around one. Take the database out of a blog and you still have pages. Take it out of a web app and nothing is left. ## Website vs web app, side by side | | Website | Web app | | --- | --- | --- | | You mainly | Read it | Use it to do work | | Content | Mostly the same for everyone | Different for each signed-in user | | Database | Small and shallow, in the background | Large, connected, and the center of the app | | Logic | Little or none | Custom rules and calculations | | Examples | Blog, menu, brochure site | YouTube, Gmail, a CRM, a quoting tool | ## Why the difference changes what you pay The words matter most when you hire someone to build one. If you ask for "a website" and you really need logins, data and rules, the quote will be wrong in both directions. Either it comes in cheap and you get a brochure, or the builder discovers the real scope halfway through. A web app costs more to build because someone has to design the data, the permissions and the logic. A website mostly needs pages and a design. Knowing which one you need is the first question to answer before you ask anyone for a price. For real numbers on the app side, read [how much it costs to replace a spreadsheet with a custom web app](https://llamapress.ai/how-much-does-it-cost-to-replace-a-spreadsheet-with-a-custom-web-app). ## Why this matters now that AI writes the code A few years ago, a custom business system meant hiring a software team for months. That is why so many businesses built a custom spreadsheet instead. Every company tracks its money, jobs and customers a little differently, and off-the-shelf software rarely fits. That has changed. People now build software by describing what they want to an AI that writes the code. So the custom spreadsheet has a new option next to it: a custom application, built around how your business actually works. But the AI is building a database-backed application whether you know it or not. If you understand the parts, you can work with it well: - **Describe it clearly.** "A table of jobs, each linked to a customer, and only managers can approve a price" gets a better result than "make me a website." - **Check what it built.** You can ask where the data lives, who can see it, and what rules run on it. - **Own the system.** You know what you have, so you can grow it, hand it to someone else, or move it later. You do not need to write code to do any of this. You need the same mental model you already use for a good workbook, applied one level deeper. ## Where your spreadsheet fits If your business runs on Excel, you are already using something close to a web app. You are just running it by hand. Your workbook has records, lookups between tabs, and formulas that act as rules. That is a database and its logic, kept in a file. The trouble starts when more people need it. Two people edit the same file. Someone sorts a column and breaks a formula. Nobody can tell which copy is current. Those are the exact problems a database and a web app were invented to solve. I wrote more about that gap in [Excel vs databases](https://llamapress.ai/excel-vs-databases-main-difference-between-spreadsheets-and-database-backed-software). So when an Excel-heavy business asks me for "a website," the answer is often a web app built from the spreadsheet they already trust. Turning a workbook into static web pages misses the point, because the value was always the data and the rules. [Static XLS to HTML converters](https://llamapress.ai/high-cost-of-static-xls-to-html-converters-vs-dynamic-web-apps) show why. ## From spreadsheet to web app We built LlamaPress to be the bridge from spreadsheet to database. You upload the workbook at [the Excel to app page](https://llamapress.ai/excel-to-app). Leonardo, our AI coding agent, reads the tabs, formulas and dropdowns. It builds a database-backed web app from it, with a login for each person on your team. An engineer reviews the build with you and checks it against your numbers. You keep what already works in Excel: the way you think about the data. You gain what a web app adds: one source of truth, private views per user, search, and rules that run without anyone babysitting a file. From Spreadsheet to Software ### See your spreadsheet as a database-backed app. Upload the workbook your business runs on. Leonardo builds a first working web app from it, and an engineer walks through it with you. [Turn My Spreadsheet Into an App](https://llamapress.ai/excel-to-app) [Talk to an Engineer](https://llamapress.ai/contact) ## Frequently Asked Questions ### What is the difference between a website and a web app? A website is something you read, like a blog or a menu, and it looks mostly the same to everyone. A web app is something you use, like Gmail or a CRM. It has logins, a large database, private data per user, and custom logic. ### Is a WordPress site a website or a web app? A typical WordPress blog is a website. It has a database for posts, pictures and comments, but that database is shallow and visitors do not sign in to their own data. Heavy plugins can push it toward a web app. ### Why does a web app cost more than a website? A web app needs its data, permissions and logic designed and built, on top of the pages. A website mostly needs pages and a design. More moving parts means more work to build and test. ### Do I need a website or a web app for my business? You need a website if people only need to learn about you. You need a web app if your team needs to sign in, share data and follow rules together. A shared spreadsheet that has outgrown itself usually means a web app.