The htaccess to Nginx Converter is a browser-based assistant that translates a deliberately narrow, auditable subset of Apache .htaccess directives into review-ready Nginx lines while surfacing every condition or unsupported rule instead of guessing. It is not a magic importer: it accepts a small, document-root .htaccess excerpt, walks one bounded line at a time, ignores RewriteEngine On, preserves comments, and emits only the directives covered by its conversion contract. Supported items are a restricted RewriteRule flag set (L, R, R=301, R=302), three non-rewrite mappings (Options -Indexes, a local ErrorDocument 404, and a quoted X-Robots-Tag Header set value), and the root-context URI slash adjustment documented in the Apache mod_rewrite introduction and the Nginx rewrite module. Everything else - RewriteCond lines, unfamiliar flags such as QSA, END, F, G, B and NC, the no-substitution dash, authentication, environment variables, proxy logic, and CMS front-controller rules - is reported as a warning with the original line number. The output is a fragment rather than a complete nginx.conf, and processing stays in the browser, which makes the htaccess to nginx on Windows workflow fit a normal local edit-test loop without sending your configuration to a server.
What the converter maps and what it intentionally surfaces as a warning
The converter is built around a small, explicit contract. Any rule outside that contract is reported with its source line number, not silently rewritten. The narrow shape is what makes an htaccess to nginx on Windows audit survivable: you can resolve each warning against the Apache and Nginx manuals instead of reverse-engineering what an automated tool produced.
| Directive or flag | How the converter treats it |
|---|---|
| RewriteEngine On | Ignored (Nginx has no equivalent directive) |
| RewriteRule pattern substitution [L] | Converted to Nginx rewrite with last flag |
| RewriteRule pattern substitution [R] | Converted to Nginx rewrite with redirect flag |
| RewriteRule pattern substitution [R=301] | Converted to Nginx rewrite with permanent flag |
| RewriteRule pattern substitution [R=302] | Converted to Nginx rewrite with redirect flag |
| RewriteCond lines | Reported as warning; the following rule is suppressed |
| Flags outside L, R, R=301, R=302 (QSA, END, F, G, B, NC, others) | Reported as warning; conversion stops for that rule |
| RewriteRule with a single dash substitution | Reported as warning; nothing emitted |
| Options -Indexes | Converted to autoindex off |
| ErrorDocument 404 /local-path | Converted to error_page 404 /local-path |
| Header set X-Robots-Tag "value" | Converted to add_header X-Robots-Tag "value" |
| Comments and blank lines | Preserved |
The "suppress the rule" behavior on RewriteCond lines is intentional. Apache conditions can inspect HTTPS state, host names, files, directories, query strings, headers, and captured groups, and the evaluation order and server architecture matter. When a RewriteRule follows a condition, emitting an unconditional rewrite could change traffic, create a loop, or expose a route. A line-numbered warning is safer than a plausible-looking but non-equivalent replacement.
Why htaccess to nginx on Windows needs its own routine
Apache and Nginx use different request-processing models. Apache .htaccess is discovered through directories and may be disabled by AllowOverride; Nginx reads centralized configuration and chooses server and location contexts before rewrite processing. Even identical regular expressions can behave differently because the string being matched, escaping, query handling, and loop behavior differ. On Windows, three practical details add to that gap.
First, the nginx.conf on a native Windows build is usually in C:\nginx\conf\nginx.conf, and many teams edit it from PowerShell, Command Prompt, Git Bash, or VS Code. Path arguments to root, error_page, and log files must use either forward slashes or escaped backslashes; the Nginx error_page directive accepts forward slashes on Windows, which avoids one source of silent breakage. Second, line endings matter: copy-pasting a Linux-style .htaccess into a Windows editor can introduce CRLF, and a stray BOM or mixed endings will produce confusing nginx -t errors. Third, running nginx -t on Windows means invoking nginx.exe from a shell where the working directory is C:\nginx; without that, nginx -t cannot find the relative include paths the configuration expects.
These details do not change what the converter does, but they shape how you assemble, validate, and reload on a Windows host. Treat the converter as an inventory assistant, not as the migration itself.
Convert a focused excerpt with the tool
The converter is built to handle one bounded task at a time: paste a small, document-root .htaccess excerpt, review the emitted lines, resolve every line-numbered warning, and only then assemble the result into nginx.conf. A focused excerpt means a few dozen lines at most - the rules that actually run in the document root, not the entire site's rewrite history.
- Open the htaccess to Nginx Converter in your browser and paste a focused document-root .htaccess excerpt (avoid nested .htaccess files, Alias mappings, and location-specific Nginx blocks).
- Confirm the converter reports how many lines it converted and how many it warned on, then read every emitted line before doing anything else.
- For each line-numbered warning, open the source line in your Apache .htaccess and resolve it manually against the Apache mod_rewrite introduction and the Nginx rewrite module documentation.
- Copy the emitted Nginx fragment (not the warnings) into the appropriate server or location context of nginx.conf on your Windows host.
- Back up the active nginx.conf, run nginx -t from C:\nginx (or your install root), fix any structural errors, then test representative requests on a local Windows instance before issuing nginx -s reload.
The five-step loop is what keeps the workflow safe. The tool never executes nginx -t, inspects installed modules, discovers include order, or accesses your server. It produces a reviewed fragment, and you do the assembly and validation in your own environment.
Place the fragment in the right Nginx context
The output is not a complete configuration. It does not create an http, server, or location block, choose a listen port, set server_name, configure TLS, locate a document root, preserve PHP routing, forward a proxy, or define logs. You have to place each reviewed line in the correct context according to the official Nginx directive documentation and the actual application architecture. The root-context slash adjustment is already applied to supported patterns - the converter inserts that leading slash for the RewriteRule flag set it covers - but the surrounding server and location blocks remain your responsibility.
The leading-slash adjustment is a documented scope assumption: it applies only to the restricted root-context RewriteRule form, not as a universal transformation for nested .htaccess files, Alias mappings, or location-specific Nginx blocks.
Permanent vs temporary redirects on a Windows staging site
Permanent redirects deserve extra care because browsers and intermediaries may cache them. On a Windows staging site, you can stage the same rewrite twice and toggle the flag to compare behavior in isolation.
| First-pass choice | Nginx flag | Cache behavior | When to switch to permanent |
|---|---|---|---|
| Temporary | redirect | Not cached by default | After old paths, new paths, query strings, alternate hosts, and HTTPS behavior all behave as expected |
| Permanent | permanent | Browsers and intermediaries may cache | Only after a confirmed, repeated staging run with the Location header inspected |
Confirm the response Location header rather than relying on the browser address bar alone. curl -I on Windows (or curl.exe in PowerShell 5.1 and PowerShell 7) prints the headers a real client receives, including the Location field. That single check is what protects you from a redirect loop that may otherwise only surface when a public user hits a cached version of the page.
Common Windows-side pitfalls when assembling the fragment
Most breakage on a Windows migration is not about the rewrite rule itself but about how the surrounding configuration is assembled. A few patterns come up often enough to flag before you issue nginx -s reload.
- Path separators. Nginx accepts forward slashes on Windows. Mixing C:\nginx\html and C:/nginx/html in the same root or error_page line is a common cause of file-not-found behavior, not configuration parse errors.
- Line endings. Save the assembled nginx.conf with consistent CRLF if your editor introduced them on paste. A stray BOM at the start of the file will produce an "unexpected token" error from nginx -t.
- Listen port collisions. Windows services and several desktop apps have historically held port 80. Bind Nginx to 8080 on staging or stop the competing service before validating.
- Reload before test. nginx -s reload on a public Windows host with an incorrect rewrite can take a site down. Always run nginx -t first, then test with curl -I on representative old paths and new paths.
- Sticky cache. A previously cached 301 can survive a configuration fix in your browser. Use a fresh profile, a private window, or curl on Windows when verifying that a temporary redirect now behaves as intended.
If the source contains authentication, authorization, hotlink protection, proxy logic, CMS front-controller rules, or complex RewriteCond conditions, treat the migration as engineering work rather than bulk text replacement. The converter is the right starting point for the inventory; it is not a substitute for the manual review those features require. For a focused audit checklist before the reload step, the audit-before-reload workflow walks through the same validation order with Windows-specific shell commands.
Related reading: Nginx Config Generator on iPhone: A Mobile Workflow.