Software & Web calculators
Choose a task below. Check each calculator’s assumptions and units before using its result.
Base64 Data URI Image Size & Overhead Calculator | AnythingOnline
Free Base64 Data URI size calculator. Calculate exact byte overhead, 33% encoding inflation, gzip compressed transfer size, and HTTP request trade-offs for inlined images.
Bcrypt & Argon2 Password Hashing Cost & Latency Calculator | AnythingOnline
Free password hashing cost calculator. Compute verification latency, maximum auth throughput per CPU core, and OWASP compliance for Bcrypt cost rounds and Argon2id parameters.
CIDR Subnet & Netmask Calculator
Calculate usable host range, broadcast address, and netmask for any IPv4 prefix.
Content Security Policy (CSP) Hash & Directive Generator | AnythingOnline
Free CSP hash generator. Compute exact SHA-256, SHA-384, and SHA-512 Base64 hashes for inline JavaScript and CSS to build secure Content-Security-Policy headers.
CSS Clamp Fluid Typography & Spacing Calculator | AnythingOnline
Free CSS clamp calculator for fluid typography and responsive spacing. Calculate exact rem and vw slope and intersection for smooth font scaling across viewports.
CSS Cubic-Bezier Transition & Easing Curve Calculator | AnythingOnline
Free CSS cubic-bezier calculator. Interactive easing curve generator, spring overshoot preview, velocity profile modeling, and CSS transition code generation.
Database Connection Pool Sizing & Queuing Latency Calculator | AnythingOnline
Free database connection pool sizing calculator. Compute optimal pool size for PostgreSQL, MySQL, and HikariCP using Brett Wooldridge formula and Little’s Law queuing theory.
DNS TTL Caching & Zero-Downtime Migration Calculator | AnythingOnline
Free DNS TTL migration calculator. Plan zero-downtime IP and server cutovers by computing pre-cutover TTL lowering timelines, resolver caching persistence, and rollback windows.
Docker & Kubernetes Container Memory & CPU Calculator | AnythingOnline
Free Docker and Kubernetes resource calculator. Calculate CPU millicores, memory reservation headroom, container OOM safety buffers, and runtime heap sizing flags.
Free Aspect Ratio Calculator & Dimension Scaler
Scale dimensions proportionally and generate responsive CSS padding percentages.
Free Conventional Commit Message Generator
Format standard semantic Git commit messages with types, scopes, and breaking changes.
Free LLM Context Window Token Budget Calculator
Allocate context window tokens across system prompts, RAG retrieval, and replies.
Free LLM Token Pricing & API Cost Calculator
Compare token and inference costs across GPT-4o, Claude 3.5, and Gemini models.
Free Password Entropy & Crack Time Calculator
Measure password strength with Shannon entropy bits and GPU brute-force crack time.
Free Unicode Bold & Italic Text Generator
Convert plain text to bold, italic, and script Unicode fonts for social media.
Free WCAG Color Contrast Ratio Checker
Test foreground and background color combinations against WCAG 2.1 AA & AAA ratios.
HTTP Cache-Control Header & CDN TTL Calculator | AnythingOnline
Free HTTP Cache-Control calculator. Calculate exact max-age seconds, s-maxage, stale-while-revalidate, and immutable directives for Cloudflare, Nginx, and Apache.
JWT Token Expiration Checker & Payload Claims Decoder | AnythingOnline
Free in-browser JWT token expiration checker and payload decoder. Check token expiry countdown, expiration timestamp, claims, and signature structure with zero network requests.
Online SVG Minifier & Path Cleaner - Reduce SVG File Size
Compress SVG graphics, remove unnecessary metadata, and round decimal precision.
Responsive Image srcset & sizes Attribute Calculator | AnythingOnline
Free responsive image srcset and sizes calculator. Generate HTML <img> and <picture> tags with w-descriptors, media query slot widths, and cellular bandwidth savings.
Subresource Integrity (SRI) Hash & Tag Generator | AnythingOnline
Free Subresource Integrity (SRI) hash generator. Generate SHA-384, SHA-256, and SHA-512 integrity hashes and HTML script and link tags for CDN security.
SVG viewBox & preserveAspectRatio Scaling Calculator | AnythingOnline
Free SVG viewBox and preserveAspectRatio calculator. Calculate SVG scaling, aspect ratios, meet vs slice letterboxing, and viewport coordinate transforms.
UNIX Cron Schedule & Next 5 Executions Calculator | AnythingOnline
Free UNIX cron expression calculator and schedule parser. View the next 5 execution dates, intervals, and plain-English natural language schedule descriptions.
Visual Cron Expression Generator & Schedule Builder
Build and decode 5-part cron schedules visually with human-readable explanations.
WebSocket Concurrent Connection & Server Memory Sizing Calculator | AnythingOnline
Free WebSocket server sizing calculator. Compute exact RAM needed for 10k to 1M concurrent connections, TCP rmem/wmem socket buffers, TLS overhead, and heartbeat egress bandwidth.