HTTP / API / Debugging

Accept Header Builder & Content Negotiation Tester

Compose clean Accept headers, tune q-values, test wildcard matching, and preview which representation a server should return. Useful for API design, browser debugging, content negotiation, and docs.

Build weighted media type preferences fast
Simulate exact, subtype wildcard, and */* fallback matching
Generate cURL, fetch, and Axios snippets

1) Build your Accept header

Preset

Media type

q-value

Parameters

Why this entry?

2) Negotiation test

Server variants (one per line)

Selection mode

Fallback when no match

Generated header

0media types

0wildcard rules

0.00average q-value

Copyable snippets

Request examples

Use application/problem+json when you want RFC 7807-style API errors.
text/* beats */* for text responses but loses to an exact type.
A q=0 token means “do not send this representation.”

Negotiation matrix

See how each server representation compares against your current client preferences.