--- obj: application website: https://aria2.github.io/ repo: https://github.com/aria2/aria2 --- # aria2 [aria2](https://aria2.github.io/) is a utility for downloading files. The supported protocols are [HTTP](../../../internet/HTTP.md)(S), [FTP](../../../internet/FTP.md), SFTP, [BitTorrent](../../../internet/BitTorrent.md), and Metalink. aria2 can download a file from multiple sources/protocols and tries to utilize your maximum download bandwidth. It supports downloading a file from [HTTP](../../../internet/HTTP.md)(S)/[FTP](../../../internet/FTP.md)/SFTP and [BitTorrent](../../../internet/BitTorrent.md) at the same time, while the data downloaded from [HTTP](../../../internet/HTTP.md)(S)/[FTP](../../../internet/FTP.md)/SFTP is uploaded to the [BitTorrent](../../../internet/BitTorrent.md) swarm. Using Metalink's chunk checksums, aria2 automatically validates chunks of data while downloading a file like [BitTorrent](../../../internet/BitTorrent.md). Aria2 can be used as a downloader by [yt-dlp](../../media/yt-dlp.md). ## Usage ```shell aria2c [] [|||] ``` ### Options | Option | Description | | -------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `-d, --dir=` | The directory to store the downloaded file. | | `-i, --input-file=` | Downloads the URIs listed in **FILE**. | | `-l, --log=` | The file name of the [log file](../../../dev/Log.md). If - is specified, log is written to stdout. If empty string("") is specified, or this option is omitted, no log is written to disk at all. | | `-j, --max-concurrent-downloads=` | Set the maximum number of parallel downloads for every queue item. | | `-V, --check-integrity [true/false]` | Check file integrity by validating piece hashes or a hash of entire file. This option has effect only in [BitTorrent](../../../internet/BitTorrent.md), Metalink downloads with checksums or [HTTP](../../../internet/HTTP.md)(S)/[FTP](../../../internet/FTP.md) downloads with --checksum option. If piece hashes are provided, this option can detect damaged portions of a file and re-download them. If a hash of entire file is provided, hash check is only done when file has been already download. This is determined by file length. If hash check fails, file is re-downloaded from scratch. If both piece hashes and a hash of entire file are provided, only piece hashes are used. Default: false | | `-c, --continue [true/false]` | Continue downloading a partially downloaded file. Use this option to resume a download started by a web browser or another program which downloads files sequentially from the beginning. Currently this option is only applicable to [HTTP](../../../internet/HTTP.md)(S)/[FTP](../../../internet/FTP.md) downloads. | | `--checksum==` | Set checksum. TYPE is hash type. The supported hash type is listed in Hash Algorithms in aria2c -v. DIGEST is hex digest. For example, setting sha-1 digest looks like this: `sha-1=0192ba11326fe2298c8cb4de616f4d4140213838` This option applies only to [HTTP](../../../internet/HTTP.md)(S)/[FTP](../../../internet/FTP.md) downloads. | | `-x, --max-connection-per-server=` | The maximum number of connections to one server for each download. Default: **1** | | `-k, --min-split-size=` | aria2 does not split less than 2\*SIZE byte range. For example, let's consider downloading 20MiB file. If SIZE is 10M, aria2 can split file into 2 range (0-10MiB) and (10MiB-20MiB) and download it using 2 sources(if --split >= 2, of course). If SIZE is 15M, since 2\*15M > 20MiB, aria2 does not split file and download it using 1 source. You can append K or M (1K = 1024, 1M = 1024K). Possible Values: 1M -1024M Default: 20M | | `-o, --out=` | The file name of the downloaded file. It is always relative to the directory given in `--dir` option. | | `-s, --split=` | Download a file using N connections. If more than N URIs are given, first N URIs are used and remaining URIs are used for backup. If less than N URIs are given, those URIs are used more than once so that N connections total are made simultaneously. The number of connections to the same host is restricted by the `--max-connection-per-server` option. See also the `--min-split-size` option. Default: 5 | | `-t, --timeout=` | Set timeout in seconds. Default: 60 | | `--check-certificate [true/false]` | Verify the peer using certificates specified in `--ca-certificate` option. Default: true | | `--http-user=, --http-passwd=` | Credentials for [HTTP](../../../internet/HTTP.md) Auth | | `--header=
` | Append HEADER to [HTTP](../../../internet/HTTP.md) request header. You can use this option repeatedly to specify more than one header:
`aria2c --header="X-A: b78" --header="X-B: 9J1" "http://host/file"` | | `--load-cookies=` | Load Cookies from FILE using the Firefox3 format (SQLite3), Chromium/Google Chrome (SQLite3) and the Mozilla/[Firefox](../../network/browsers/Firefox.md)(1.x/2.x)/Netscape format. | | `--save-cookies=` | Save Cookies to FILE in Mozilla/[Firefox](../../network/browsers/Firefox.md)(1.x/2.x)/ Netscape format. If FILE already exists, it is overwritten. Session Cookies are also saved and their expiry values are treated as 0. | | `-U, --user-agent=` | Set user agent for [HTTP](../../../internet/HTTP.md)(S) downloads. Default: `aria2/$VERSION`, $VERSION is replaced by package version. | | `-S, --show-files [true/false]` | Print file listing of ".torrent", ".meta4" and ".metalink" file and exit. In case of ".torrent" file, additional information (infohash, piece length, etc) is also printed. | | `--select-file=...` | (Torrent) Set file to download by specifying its index. You can find the file index using the `--show-files` option. Multiple indexes can be specified by using `,`, for example: `3,6`. You can also use `-` to specify a range: `1-5`. `,` and `-` can be used together: `1-5,8,9`. |