HTML5 Viewer

HTML Editor is a focused native Mac app for the last mile of shipping to the App Store: writing and polishing HTML, previewing it on real device screens, and turning it into every screenshot size Apple asks for.

NEW IN 2.0 — DEVICE PREVIEW. See your page on an iPhone, iPad or Mac screen at its true width, then capture a pixel-exact App Store screenshot in one click.

DEVICE PREVIEW

• Preview inside iPhone 6.9-inch, 6.5-inch and 6.3-inch, iPad Pro 13-inch and Mac screens.
• True CSS widths, so your responsive breakpoints fire exactly as on the hardware.
• Rotate to landscape. Force light or dark mode to test prefers-color-scheme.
• A 9:41 status bar, coloured from your page's theme-color.
• Capture (Shift-Cmd-K) renders at the device's real pixel density: 1320 × 2868, 1242 × 2688, 2064 × 2752, 2880 × 1800. No resizing, no blur.
• Captures open in the Screenshot Composer with the device frame, background and headline ready. Or save every App Store size into a folder in one go.

THE EDITOR

• Open any .html, .htm, .css, or .js file.
• See it rendered instantly in a live WebKit preview next to your code.
• HTML syntax highlighting — tags, attributes, strings, comments.
• Line numbers that stay readable at every font size.
• Monospace font with adjustable size from 10 to 24 points.
• Word wrap toggle, built-in find bar, multi-level undo.
• Open and save with standard macOS file dialogs.
• Keyboard shortcuts: Cmd-N new, Cmd-O open, Cmd-S save, Shift-Cmd-S save as.

No dev server, no Node, no build step, no login. Just a native window and your file.

THE SCREENSHOT CONVERTER

Drag your screenshots in, pick a device, press Export. Every App Store Connect screenshot size Apple asks for is built in:

• iPhone — 6.9-inch (16 Pro Max), 6.7-inch, 6.5-inch, 5.5-inch, 4.7-inch
• iPad — 13-inch (M4), 12.9-inch, 11-inch, 10.5-inch
• Mac — 2880×1800, 2560×1600, 1440×900, 1280×800
• Apple Watch — Ultra 49mm through Series 3 40mm
• Apple TV — HD and 4K
• Apple Vision Pro
• Custom — any width × height in pixels

Three fit modes:
• Fit — letterbox with a background color of your choice
• Fill — scale and crop to fill the frame
• Stretch — exact target dimensions

Export to PNG or JPEG with an adjustable quality slider. Batch-process a whole folder in one pass. Output files are auto-named with the target dimensions, ready to upload.

PRIVACY, BY DEFAULT

HTML Editor runs entirely on your Mac.

• No accounts, no sign-in, no profiles.
• No analytics, no telemetry, no third-party SDKs, no advertising.
• No network requests made by the app itself.
• Files stay on your Mac — the app runs in Apple's sandbox with only user-selected file access.
• Screenshot conversion happens on-device with Core Graphics.

Your code is your code. Your screenshots are your screenshots.

REQUIREMENTS

macOS 14 Sonoma or later. Universal binary — runs natively on Apple Silicon and Intel.