Networking / IP Tools — CIDR, Subnets, Ranges
Five browser-local utilities: subnet calculator, IP address converter, range→CIDR, CIDR summarize, and IP-in-subnet checks. IPv4 and IPv6 from day one. Also useful: number-base-converter for numeric bases (not CIDR math).
- Calculate subnets and usable host ranges (IPv4/IPv6).
- Convert addresses and summarize CIDR lists.
- Check whether an IP sits inside a network block.
Subnet Calculator
IPv4/IPv6 network, mask, hosts, and address class — browser-local.
IP Address Converter
IPv4/IPv6 decimal, hex, binary, compress/expand — local forms.
IP Range to CIDR
Minimal exact CIDR cover for an inclusive start–end range.
CIDR Summarize
Merge or dedupe CIDR lists with fail-fast validation.
IP in Subnet
Check IP ∈ CIDR or whether two CIDRs overlap.
Guides
Web Performance Checklist 2026 — 6 Pillars to Audit
A 2026 checklist: minify JS/CSS/HTML, Brotli, images, cache, network, then LCP, INP and CLS thresholds with actions in order.
Critical CSS: Extract, Minify and Inline for LCP
Extract above-the-fold CSS, minify the block, inline it in the head, then load the rest async. How it helps LCP without shipping all styles first.
Optimize REST API Performance with JSON Minification
Speed up your REST APIs by optimizing JSON payloads. Minification, compression, pagination and best practices for ultra-fast APIs.
Why Fast Sites Rank Better on Google: The Link Between Speed and SEO
Discover why Google favors fast sites in search results. Understand the link between web performance and SEO, and learn how to optimize your site to improve your ranking.
Apache & Nginx GZIP/Brotli Config — Step-by-Step Guide
Enable GZIP and Brotli on Apache (mod_deflate) and Nginx (ngx_brotli). Copy-paste configs, set MIME types, and verify with DevTools or online checkers.
Improve Core Web Vitals with Minification (2026)
Update for 2026: minify JavaScript and CSS to support LCP, INP and CLS. What minification does—and what it cannot fix alone.