Web development
The small tools that make building for the web a little easier.
Chmod calculator
Tool: Web developmentConvert Unix permission modes into readable permissions and a ready-to-copy command.
CIDR range combiner
Tool: Web developmentCombine overlapping or adjacent address ranges into the smallest equivalent CIDR list.
Content Security Policy builder
Tool: Web developmentBuild a policy from explicit directives and check common unsafe settings.
Cron builder and explainer
Tool: Web developmentPreview the next occurrences of a five-field cron expression.
CSS formatter and minifier
Tool: Web developmentFormat or minify CSS without executing it.
CSS selector tester
Tool: Web developmentFind matching elements in pasted HTML without rendering the supplied page.
CSS specificity calculator
Tool: Web developmentCompare the specificity of CSS selectors.
cURL and Fetch converter
Tool: Web developmentTurn a supported cURL request into a readable Fetch snippet without sending it.
Font size converter
Tool: Web developmentConvert a pixel font size to REM and points instantly. Starts with a 16px root font size.
Gitignore builder
Tool: Web developmentCombine locally bundled ignore rules for a project.
HTML formatter
Tool: Web developmentFormat HTML source while preserving whitespace-sensitive content.
HTML link extractor
Tool: Web developmentExtract links and their labels from pasted HTML.
HTML table extractor
Tool: Web developmentExtract a selected HTML table into rows and CSV.
HTML to plain text
Tool: Web developmentExtract readable text from HTML while retaining useful line breaks.
HTTP header inspector
Tool: Web developmentInspect pasted HTTP headers and identify duplicate or malformed fields.
IP subnet calculator
Tool: Web developmentFind network boundaries and address counts for an IPv4 or IPv6 CIDR.
JavaScript formatter and minifier
Tool: Web developmentFormat or minify JavaScript source without running the program.
Meta-tag builder and preview
Tool: Web developmentGenerate escaped page and social metadata from your title and description.
Redirect rule generator
Tool: Web developmentGenerate permanent redirect rules from one source and destination pair per line.
Regex tester
Tool: Web developmentFind matches, inspect capture groups and test replacements using JavaScript regular expressions.
Responsive image markup builder
Tool: Web developmentGenerate picture and srcset markup from an image naming pattern.
Robots.txt builder and tester
Tool: Web developmentTest whether a supplied robots.txt permits a crawler to visit a URL.
Semantic version range tester
Tool: Web developmentCheck which semantic versions satisfy a package version range.
Sitemap builder and validator
Tool: Web developmentCreate a sitemap from URL lines or inspect a pasted XML sitemap.
SQL formatter
Tool: Web developmentFormat SQL using the selected database dialect.
URL parser and builder
Tool: Web developmentInspect a URL and edit its path, query parameters or fragment.
Web app manifest generator
Tool: Web developmentCreate an installable web application manifest from explicit settings.
Chmod calculator
Convert Unix permission modes into readable permissions and a ready-to-copy command.
CIDR range combiner
Combine overlapping or adjacent address ranges into the smallest equivalent CIDR list.
Content Security Policy builder
Build a policy from explicit directives and check common unsafe settings.
Cron builder and explainer
Preview the next occurrences of a five-field cron expression.
CSS formatter and minifier
Format or minify CSS without executing it.
CSS selector tester
Find matching elements in pasted HTML without rendering the supplied page.
CSS specificity calculator
Compare the specificity of CSS selectors.
cURL and Fetch converter
Turn a supported cURL request into a readable Fetch snippet without sending it.
Font size converter
Convert a pixel font size to REM and points instantly. Starts with a 16px root font size.
Gitignore builder
Combine locally bundled ignore rules for a project.
HTML formatter
Format HTML source while preserving whitespace-sensitive content.
HTML link extractor
Extract links and their labels from pasted HTML.
HTML table extractor
Extract a selected HTML table into rows and CSV.
HTML to plain text
Extract readable text from HTML while retaining useful line breaks.
HTTP header inspector
Inspect pasted HTTP headers and identify duplicate or malformed fields.
IP subnet calculator
Find network boundaries and address counts for an IPv4 or IPv6 CIDR.
JavaScript formatter and minifier
Format or minify JavaScript source without running the program.
Meta-tag builder and preview
Generate escaped page and social metadata from your title and description.
Redirect rule generator
Generate permanent redirect rules from one source and destination pair per line.
Regex tester
Find matches, inspect capture groups and test replacements using JavaScript regular expressions.
Responsive image markup builder
Generate picture and srcset markup from an image naming pattern.
Robots.txt builder and tester
Test whether a supplied robots.txt permits a crawler to visit a URL.
Semantic version range tester
Check which semantic versions satisfy a package version range.
Sitemap builder and validator
Create a sitemap from URL lines or inspect a pasted XML sitemap.
SQL formatter
Format SQL using the selected database dialect.
URL parser and builder
Inspect a URL and edit its path, query parameters or fragment.
Web app manifest generator
Create an installable web application manifest from explicit settings.