curl vs wget

curl-vs-wget.md

wget and curl both fetch data over the network, but they have different design goals. The simplest way to remember it:

wget = download files curl = talk to services

Below is the clean mental model, then details.

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1️⃣ Core philosophy (the “why”)

wget

• Built to download files
• Fire-and-forget
• Great for scripts that need files no matter what

curl

• Built to transfer data
• Designed for APIs, testing, automation
• Think: HTTP client toolkit

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2️⃣ Basic usage comparison

Download a file

wget https://example.com/file.iso

curl -O https://example.com/file.iso

Both work. But wget is simpler and more resilient by default.

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3️⃣ Key differences (practical table)

Feature	wget	curl
Default use	File downloading	Data transfer
Recursive download	✅ Yes	❌ No
Resume downloads	✅ Yes	⚠️ Manual
Mirrors support	✅ Yes	❌ No
API requests	⚠️ Limited	✅ Excellent
HTTP methods (POST, PUT, DELETE)	❌ Weak	✅ First-class
JSON headers	❌ Awkward	✅ Easy
Output to stdout	❌ No (by default)	✅ Yes
Libraries	❌ CLI-only	✅ libcurl
Installed by default	Often	Almost always

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4️⃣ Why sysadmins love wget

Resumable downloads (killer feature)

wget -c https://example.com/large.iso

If the connection drops → it resumes.

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Recursive downloads

wget -r https://example.com/docs/

curl cannot do this.

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Mirror a website

wget --mirror --convert-links https://example.com

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5️⃣ Why engineers love curl

APIs (this is curl’s home turf)

curl https://api.github.com

POST JSON:

curl -X POST https://api.example.com/login \
  -H "Content-Type: application/json" \
  -d '{"user":"bob","pass":"secret"}'

This is painful or impossible with wget.

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Inspect headers

curl -I https://example.com

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Debug TLS / HTTP

curl -v https://example.com

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Pipe data

curl https://example.com/script.sh | bash

wget writes to disk by default; piping is awkward.

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6️⃣ Behavior differences that trip people up

Output destination

• wget → file
• curl → stdout

curl https://example.com > file.txt

or:

curl -o file.txt https://example.com

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Error handling

• curl fails loudly
• wget retries automatically

This is why wget is better for flaky networks.

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7️⃣ Which should you use?

Use wget when:

• Downloading ISOs
• Fetching large files
• Mirroring content
• You want retries + resume automatically
• Writing simple install scripts

Proxmox ISO? → wget

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Use curl when:

• Talking to REST APIs
• Testing HTTP endpoints
• Sending JSON
• Inspecting headers
• Scripting complex requests

API / web service? → curl

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8️⃣ One-line rule to memorize

wget gets files. curl talks to servers.

If you follow that rule, you’ll almost never pick the wrong tool.

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9️⃣ Bonus: common myth

“curl can replace wget”

Technically yes. Practically no.

You can download files with curl — but you’ll keep re-implementing features wget already solved.

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If you want, I can give you:

• A wget vs curl cheat sheet
• A “convert wget → curl” map
• Real-world examples (Proxmox, cloud-init, APIs)

Just say the word.