Flash Download

Flash Download is a desktop download manager (built with Electron) for Linux, Windows and macOS. It opens up to 32 connections against one file, and each connection can go out a different proxy route.

• Progress per connection: no single overall bar. Each connection gets its own row, as wide as the bytes it has taken, with its own speed beside it, so you can see which route is slow or which proxy went bad.
• Live rebalancing: a connection that finishes takes over the back half of whichever part has the longest time left, so the slowest connection doesn't hold up the end.
• Resume: progress is saved every 2 seconds, so pausing or quitting picks up from the exact byte. A resume is refused if the file on the server changed (its ETag moved).
• SHA-256 check: the finished file is verified with SHA-256.
• Routes: direct, an HTTP proxy, or SOCKS4/5. Proxy passwords are encrypted with your system's credential store.

Latest release: 0.1.1 (2 October 2026). It adds macOS builds for Apple Silicon and Intel; everything else is unchanged from 0.1.0. The download is one archive with every platform's files; see the Releases tab.

Install

Linux

• .deb (recommended on Debian/Ubuntu): sudo apt install ./flash-download_0.1.1_amd64.deb. It sets up Chromium's sandbox while installing, so the app runs fully sandboxed.
• AppImage: chmod +x it, then run it. Starting it from your applications menu works; from a terminal, add --no-sandbox: ./flash-download-0.1.1-x86_64.AppImage --no-sandbox (why: see the FAQ below).

Windows

• Installer (flash-download-0.1.1-setup.exe): installs for your user, in a folder you choose.
• Portable (flash-download-0.1.1-portable.exe): runs without installing.

macOS (11 or later)

• Pick the .zip for your Mac: mac-arm64 (Apple Silicon) or mac-x64 (Intel).
• The app is unsigned, so open it the first time with right-click → Open, or run xattr -dr com.apple.quarantine on the app in Terminal.

How to use it

1. Add a download: paste a link into Paste a link to start at the top. With Offer links copied to the clipboard on (Settings), the app offers a link as soon as you copy it. A browser or file manager can also hand a link straight to the app.
2. Choose how: in the add dialog, set Save as, Folder, Connections (up to 32) and the Route: direct, one proxy, or Spread across pool, where each connection takes a different healthy route. Tick Verify SHA256 after stitching if you want the check. Then Start now or Add to queue.
3. Watch the connections: one bar per connection, with its own speed. When a proxy goes bad you see a short hatched bar with the route's name on it.
4. Pause and resume: pause any time, or just quit; it carries on from the same bytes.

Add proxy routes

Open Routes (the route pool) → Add a route: a name, the type (HTTP, SOCKS4, SOCKS5), host and port, and an optional username and password. A new route is tested straight away and its latency shown. Three failures inside a minute mark a route degraded, and its connections move to other routes without stopping the download.

Settings

Settings has where downloads are saved (Save downloads to), the default number of connections, how many downloads run at once, a Speed limit in MB/s shared across all connections, and whether to verify the checksum when a download finishes.

Also inside JJ Bot

Since JJ Bot 0.3.93, Flash Download is also a JJ Bot tool. Install it from JJ Bot's Marketplace → Tools for a Downloads page: files come down over up to 32 connections, keep going after JJ Bot restarts, and are checked with SHA-256. Your bots can start downloads too (after your OK), wait for them, and carry on with the files. Per-connection proxies are a desktop-app feature for now. About JJ Bot →

FAQ

Why are several connections faster?

The file is split into parts and each connection fetches its own part at the same time, so the total isn't held to what one connection can get. A download only ends when its slowest part does, which is why Flash Download keeps handing what's left to connections that have finished.

What if a server doesn't allow ranges?

Before it starts, the app asks the server for a single byte to learn the size and whether it honours ranges. If it doesn't, you get one honest stream over a single connection rather than a fake parallel one.

Where do my files go?

To your system's Downloads folder by default. Change it in Settings → Save downloads to, or pick a Folder for each download.

The AppImage won't start on Linux and mentions the SUID sandbox

The AppImage is mounted over FUSE with nosuid, so its chrome-sandbox helper can never be owned by root, and on systems without the namespace sandbox Chromium stops. The applications-menu entry already passes --no-sandbox; from a terminal, add it yourself. That turns off Chromium's sandbox for this AppImage only (the window loads no remote content). For the full sandbox, use the .deb.

Is it signed? Does it update itself?

Not yet: the builds are unsigned and there is no auto-updater. New versions are posted under this page's Releases tab.

What can't it do?

• HTTP and HTTPS only; no torrent or metalink sources yet.
• No scheduler, no browser-extension capture, no per-site route rules.
• Up to 32 connections per file.