Speedtest CLI using Linux tools only, requires SSH server

speedtest

#!/bin/bash
set -euo pipefail
IFS=$'\n\t'

# Elegant way to test internet speed on the CLI.
# Mostly from https://superuser.com/a/70400/256215
#
# Does not require large files on a server,
# but requires SSH access to a remote machine.
#
# Replace myserver.com with an SSH server where
# $USER has acces, ideally without password,
# i.e. through key exchange.
# 
# Using `pv` between `dd` and `ssh` is optional,
# but gives nice progress information.

dd if=/dev/zero bs=50MB count=1 \
    | pv --size 50M --timer --eta --rate --bytes \
    | ssh myserver.com 'cat > /dev/null'

To go fancy, with coloured output etc.:

#!/bin/bash                                                                                                           
set -euo pipefail
IFS=$'\n\t'

SIZE=100M
HOST=myserver.com
TEXT="sending ${SIZE} to ${HOST}"

dd if=/dev/zero bs="${SIZE}" count=1 2>/dev/null \
    | pv --size	"${SIZE}" --bytes --interval 0.2 --name "${TEXT}" \
      --format ' %{timer} %{sgr:green}%{transferred}%{sgr:reset} %{sgr:green,bold}%{rate}%{sgr:reset} %{sgr:gray,dim}%{eta}%{sgr:reset}' \
      --extra-display 'window:speedtest: %t %b %r %e' \
      --stats \
    | ssh "${HOST}" 'cat > /dev/null'