Nginx Location Matching Lab
Paste a server block or a flat list of location rules, enter a URI, and see which Nginx location wins through a five-step decision trace.
Nginx Location Matching Lab
Paste a server block or a flat list of location rules, enter a URI, and see which Nginx location wins through a five-step decision trace.
How Nginx chooses a location
Selection is a sequence, not a specificity score
Nginx first checks exact matches, remembers the longest matching prefix, may stop on ^~, then tests regular expressions in configuration order. If no regex wins, it returns to the remembered prefix.
A focused model of common location syntax
The parser accepts one server block or a flat list of locations using =, ^~, plain prefixes, ~, and ~*. It deliberately rejects nested and named locations, and browser regular expressions cannot reproduce every PCRE feature used by Nginx.
Safe, local configuration experiments
Parsing and matching happen entirely in the browser. No Nginx process runs, no request is sent, and pasted hostnames, paths, or internal configuration stay on your device.
FAQ
Common questions and answers about this topic.
How do I use the Nginx Location Matching Lab?
Paste one server block or a flat set of location directives, enter a URI beginning with /, and read the five-step trace. The selected rule and every skipped or continued stage update as you edit.
Do Nginx locations use the order written in the file?
Only regex locations depend directly on configuration order: the first matching regex wins. Exact and prefix locations follow their own rules, including exact-match priority and longest-prefix selection.
What does ^~ change in location matching?
^~ is still a prefix location. If it is the longest matching prefix, Nginx selects it without checking regex locations. A shorter ^~ prefix does not beat a longer matching plain prefix.
Why does the first regular expression win instead of the most specific one?
Nginx tests regex locations in the order they appear and stops at the first match. Reordering two overlapping regex locations can therefore change the selected configuration.
Does this exactly reproduce every Nginx configuration?
No. It models one server block with flat locations and common =, ^~, prefix, ~, and ~* behavior. It does not execute directives, nested or named locations, rewrite or try_files redirects, or every PCRE feature.
Is it safe to paste an internal Nginx configuration?
The parser runs entirely in your browser and does not upload the configuration or send the test request. Still review your organization's screen-sharing, clipboard, and device policies before handling sensitive configuration.