File & Byte Utilities

File size formatting, extension extraction, and MIME type helpers in sc-fns/file.

The sc-fns/file module provides helpers for parsing file paths, extensions, formatting byte counts, and media type detection.

ts
import {
    getFileExtension,
    getFileName,
    formatFileSize,
    isImage,
    isVideo,
    isPDF,
} from "sc-fns/file";

`formatFileSize`

Converts a byte count into a human-readable size string (B, KB, MB, GB, TB, PB).

Signature

ts
function formatFileSize(bytes: number, decimals?: number): string; // Default decimals: 2

Examples

ts
formatFileSize(512); // "512 B"
formatFileSize(1024); // "1 KB"
formatFileSize(1024 * 1024 * 4.5); // "4.5 MB"
formatFileSize(10737418240); // "10 GB"

`getFileExtension`

Extracts the lowercase file extension from a filename or path without the leading dot.

Signature

ts
function getFileExtension(filename: string): string;

Examples

ts
getFileExtension("report.final.PDF"); // "pdf"
getFileExtension("/var/data/archive.tar.gz"); // "gz"
getFileExtension("noextension"); // ""

`getFileName`

Extracts the basename from a file path, with an option to include or exclude the extension.

Signature

ts
function getFileName(path: string, includeExt?: boolean): string; // Default includeExt: true

Examples

ts
getFileName("/uploads/images/avatar.png"); // "avatar.png"
getFileName("/uploads/images/avatar.png", false); // "avatar"

Media Guards: `isImage`, `isVideo`, `isPDF`

Tests if a filename, extension, or MIME type represents an image, video, or PDF document.

Examples

ts
isImage("photo.jpeg"); // true
isImage("image/png"); // true
isImage("presentation.pptx"); // false
 
isVideo("trailer.mp4"); // true
isVideo("video/webm"); // true
 
isPDF("contract.pdf"); // true
isPDF("application/pdf"); // true

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Last updated on October 25, 2026

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