Check if a File Exists in Node.js
The easiest way to check whether a file exists in Node.js is using the fs/promises module's access() function.
The access() function returns a promise that rejects if the file does not exist.
With await, await fsPromise.access(filename) will throw an error if the file does not exist.
const fsPromises = require('fs/promises');
async function run() {
// Works, returns undefined
await fsPromises.access(__filename);
// Throws "Error: ENOENT: no such file or directory"
await fsPromises.access('./some-file-that-does-not-exist');
}
run().catch(err => {
console.error(err);
process.exit(-1);
});Legacy Alternatives
In older Node.js projects, you may see the fs module's exists() or existsSync() functions used instead.
exists() is currently deprecated, so we do not recommend using it.
existsSync() is not currently deprecated. However, existsSync() is synchronous, which means you should never use it in any transactional code, like Express route handlers.
You may use existsSync() in scripts for convenience, but you should prefer to use fsPromises.access() unless you have a good reason to use existsSync().