Help

How to get UwView and the basics of using it. UwView is a read-only text viewer (no editing).

Get it / download

Get the latest build from GitHub Releases. Pick the file for your OS and architecture.

To try it with no install, use the browser WASM demo (Chromium-based browsers recommended).

Install / launch

• macOS: unzip and launch UwView.app. The free build is unsigned, so the first launch may be blocked — right-click UwView.app → Open → choose Open in the dialog.
• Windows: unzip and run UwView.exe. If SmartScreen warns, choose More info → Run anyway.
• Linux: extract the tar.gz, make UwView executable (chmod +x UwView) and run ./UwView.

Basics

• Open a file: use “Open…” on the start screen, or drag & drop onto the window (multi-select for a batch add).
• Tabs: multiple files open as tabs; each tab has its own index.
• Jump: enter a line number in line mode, or a ratio like 50% in page mode (while indexing).
• Scroll: wheel, ↑↓, PageUp / PageDown, Home / End, and the vertical scrollbar.
• Encoding: auto-detect or switch manually from the toolbar dropdown; switching applies instantly with no re-indexing.

Search

• Literal and regular-expression search. Search runs as a background scan independent of the index and can be cancelled midway.
• Matches are highlighted on visible lines, and the minimap shows the hit distribution across the whole file (click to jump).
• When a search finishes, a popup lists the matching lines. Double-click / Enter jumps to the line in the main view; it can show surrounding context and save just the matching lines to a separate file.
• The search box autocompletes from input history (up to 50). Save frequent searches with “★” and run them from the dropdown.

Color highlighter

Independently of search, colorize multiple registered patterns at once. Supports regex, case-insensitive, and whole-line / match-only coloring, with a color-blind-friendly 32-color palette. Save named sets and export/import them as .uwvhl, and use the 7 bundled presets (generic log / syslog・Linux / Web access / JSON / GNSS NMEA / GeoJSON / KML). You can also select a word and right-click → color swatch to colorize it instantly (highlighters are kept per tab).

Other features

• Bookmarks: toggle any line and jump prev/next. They survive encoding switches and show in blue on the minimap.
• Real-time Tail: detects appends and auto-scrolls to the end; opens logs that other processes are still writing.
• Session restore, recent files & favorites: on a normal launch it asks “Restore the previous files?”; recent files (up to 15) and favorites open from the start screen.

UwView Pro — activating your license

If you bought UwView Pro, a license key starting with UVP-… arrives from Polar after purchase. Open the app, go to Settings → License, paste the key, and activate to enable the Pro features (instant second open with line numbers, faster search, .uwvz archive, block selection). Available for Windows, macOS and Linux (one license, every OS).

Known limitations

• Line breaks: LF / CRLF are supported (lone-CR classic-Mac format is not).
• UTF-16 is recognized by BOM, but line splitting is \n-based, so the primary targets are UTF-8 / Shift-JIS / EUC-JP.
• The literal fast-path can, rarely, produce a false hit straddling a character boundary in Shift-JIS; use regex mode when you need strictness.
• The browser build needs a file chosen each time (no direct path open / drag & drop / Tail), and indexes more slowly than native.

Need help?

For bugs or questions, see Support. Feature requests and the roadmap are public at GitHub Issues.

From the developer: a list of my apps, Kindle books and open-source projects is on GitHub: amru195704.