Elysia Tools

Browse tools, examples, visual explainers, and topic guides from one clear workspace.

Top Categories

Hubs

Language
ZHESPTRUFRDEEN

Elysia Tools

Navigation

Development

HTTP Cache-Control CDN Edge TTL Budget Optimizer

· Last updated：2026-08-06

Analyze Cache-Control directives, calculate browser/shared-cache TTL and stale budgets, detect directive conflicts, and compare static behavior notes for generic HTTP, Fastly, Cloudflare, and Akamai.

Execution

Run this tool

Fill in the form, run the tool, and review the result in one place.

Samples

Examples that match this tool

Related

Continue with connected tools and hubs

Written by the Elysia Tools team

Tool usage guide

Learn when to use this tool, what it supports, and how real users apply it.

Key facts

Category
Development
Input types
textarea, select, number
Output type
html
Sample coverage
4
API ready
Yes

Overview

Analyze an HTTP Cache-Control header to calculate browser and shared-cache TTLs, review stale budgets, detect directive conflicts, and compare static behavior notes for generic HTTP, Fastly, Cloudflare, and Akamai.

When to use

  • Check whether browser and CDN freshness periods match your caching requirements.
  • Compare max-age, s-maxage, stale-while-revalidate, and stale-if-error budgets with defined limits.
  • Investigate conflicting directives such as private, public, no-cache, and no-store.

How it works

  1. 1Enter a Cache-Control header, such as `public, max-age=60, s-maxage=600, stale-while-revalidate=30`.
  2. 2Select a CDN context or use Generic HTTP for a general analysis.
  3. 3Optionally enter browser TTL, edge TTL, and stale budgets in seconds.
  4. 4Review the calculated TTLs, stale windows, directive conflicts, and static CDN behavior notes.

Use cases

  • Validate cache headers for public web pages and APIs before deployment.
  • Set separate browser and edge freshness budgets for CDN-delivered content.
  • Review stale serving behavior and cache directive conflicts during performance or reliability audits.

Examples

1. Separate browser and edge freshness budgets

Web performance engineer

Background

A team serves public content with a short browser freshness period, a longer CDN edge period, and a limited stale-while-revalidate window.

Problem

They need to confirm that the Cache-Control values stay within their browser, edge, and stale budgets.

How to use

Enter the header and select Cloudflare, then provide the three optional budgets.

Cache-Control: `public, max-age=60, s-maxage=600, stale-while-revalidate=30`; CDN: Cloudflare; browser TTL budget: 120 seconds; edge TTL budget: 900 seconds; stale budget: 60 seconds.

Outcome

The analysis separates the browser and shared-cache TTLs, checks the stale window, and reports any conflicts or budget issues.

2. Check a no-cache response policy

API developer

Background

An API response is marked private and no-cache because it should not provide a normal freshness period for browser or shared caching.

Problem

The developer wants to verify that the policy produces no browser or edge freshness TTL.

How to use

FAQ

What input does this tool require?

Enter a Cache-Control header in the required text field.

What does max-age represent?

max-age specifies the freshness lifetime for browsers and other private caches, in seconds.

What does s-maxage represent?

s-maxage specifies the freshness lifetime for shared caches such as CDN edge caches, in seconds.

Can I check stale-while-revalidate and stale-if-error?

Yes. The analyzer reviews stale directives and compares their budgets when you provide a stale budget.

Which CDN options are available?

You can select Generic HTTP, Fastly, Cloudflare, or Akamai for static behavior notes.

Hub

HTTP Cache Policy Change Review and Evidence Handoff

Define cache test cases, compare real response headers before and after a change, review TTL budgets and deliver redacted evidence with approval and rollback conditions.

Home
Tools3201
Samples593
Visualizations465
Viewers103
Hubs233
Tags333
Images, Audio & Video657

Image, audio, and video processing, conversion, and optimization tools

Math, Date & Finance644

Calculators, numerics, date logic, statistics, and finance tools

Design & Color297

Color, layout, graphics, visual styling, and design helper tools

Text & Writing209

Writing, cleanup, formatting, extraction, and text analysis tools

Developer & Web193

Developer utilities, networking, web debugging, and automation helpers

Conversion & Encoding175

Format, file, archive, unit, and encoding conversion tools

FLAC/WAV Source Screening and Evidence Handoff
Self-Hosted Giveaway Widget Review and Embed Handoff
Stripe Promo Code Batch Review and Import Preflight
Batch Photo Culling Review and Editing Shortlist Handoff
UI Screenshot Structure Review and Development Handoff

© 2026 Elysia Tools. All rights reserved.

DocsPricingAboutTerms of ServicePrivacy PolicyCookiesContact
Java

Android Image Processing Java Samples

Android Java image processing examples including reading/saving images, scaling, and format conversion

Kotlin

Android Image Processing Kotlin Samples

Android Kotlin image processing examples including reading/saving images, scaling, and format conversion

Python

Web Image Processing Python Samples

Web Python image processing examples using PIL/Pillow including reading, saving, resizing, and format conversion

Objective-C

macOS Image Processing Objective-C Samples

macOS Objective-C image processing examples including image reading/saving, image scaling, and format conversion

Math & Numbers

Pump NPSH (Net Positive Suction Head) Calculator & Cavitation Check

Compute the available Net Positive Suction Head (NPSH_a) of a pump and compare it against the required NPSH (NPSH_r) from the pump curve. Head-balance form: NPSH_a = (p_surface_abs - p_vapor) / (ρ·g) + H_static - h_friction. Surface and vapor pressures are absolute; H_static is positive for flooded suction, negative for suction lift. Returns margin (NPSH_a - NPSH_r), ratio (NPSH_a/NPSH_r) and a classification: safe, marginal (margin < 0.5 m), or cavitation likely. If NPSH_r = 0, only NPSH_a is reported. Pressure in Pa/kPa/bar/atm/psi, length in m/ft, density in kg/m³/g/cm³/lb/ft³.

Astronomy

ESA PB05-Style Brouwer–Lyddane Averaged-Element Orbit Propagator (J2–J6 + Luni-solar)

Propagate near-Earth and GNSS-region orbits with a semi-analytical averaged-element model in the Brouwer–Lyddane / PB05 tradition: orbit-averaged secular drift of the mean elements under the EGM96 zonal field J2–J6 (numerical Gauss-equation averaging — the Delaunay-normalisation analogue with the closed-form J2 rates as a built-in cross-check), first-order J2 short-period mean↔osculating reconstruction, long-period J3 frozen-orbit analysis (e = −J3·sin i/(2·J2·p), ω = 90°), double-averaged luni-solar quadrupole secular effects on an elliptical inclined perturber orbit (the Celletti/Kozai–Lidov term with the 39.23° critical mutual inclination), tesseral ground-track resonance checks (1:1, 2:1, 3:2, 5:2 and small-rational commensurabilities with Earth rotation), sun-synchronous inclination solving, and an in-report RK4 numerical-propagation cross-validation of the averaged model.

Data Analysis

Correlation Analyzer

Advanced correlation analysis tool that calculates correlation coefficients between variables to measure the strength and direction of their linear relationships. Perfect for statistical analysis, financial modeling, scientific research, and data exploration. Features: - Multiple correlation methods (Pearson, Spearman, Kendall) - Correlation matrix generation - Statistical significance testing (p-values) - Confidence intervals calculation - Heatmap visualization - Scatter plot matrix generation - Missing value handling strategies - Outlier detection and handling - Group analysis capabilities - Detailed statistical reports Common Use Cases: - Financial market analysis and risk assessment - Scientific research and hypothesis testing - Customer behavior and marketing analysis - Healthcare and medical data analysis - Quality control and process optimization - Educational performance evaluation

Development

Responsive Picture / srcset Art Direction Builder

Build complete <picture> markup with art-directed crops: per-breakpoint <source media> elements, 1x/2x density candidates or {w}-template width descriptors, optional AVIF/WebP format layers, sizes handling, CLS-safe width/height, plus HTML and JSX flavors with spec-based lint notes.

Enter the header, keep the CDN selection as Generic HTTP, and set the browser, edge, and stale budgets to zero.

Cache-Control: `private, no-cache`; CDN: Generic HTTP; browser TTL budget: 0 seconds; edge TTL budget: 0 seconds; stale budget: 0 seconds.

Outcome

The analysis confirms that no browser or edge freshness TTL is available and highlights the cache policy for review.