toolooo · ToolboxTurn invisible problems
into visible ones.
Small browser tools that help you check, simulate, decide, plan and create. Useful, fast, beautiful — no signup, no backend, no bullshit.
Every tool answers one of these questions
Click a family to filter the tools below.
How deep does the tool go?
Levels describe experience maturity. Every current production tool targets LV2.
Input → Calculate → Result
Explore → See → Understand → Act
Connected workflows and deeper Toolooo experiences
Showing 40 of 40
API Payload Doctor
Paste an API request or response and get a structured diagnosis of what could go wrong with it.
JWT Time Machine
Decode a JWT and see its issued/valid/expiry claims plotted on an actual timeline.
CORS Doctor
Diagnose exactly which CORS rule is blocking a request, and why.
Print Ready Doctor
Check a photo or document against real print sizes and see exactly how sharp it will look at each one.
Schema Drift Doctor
Compare JSON or CSV samples and see where a data contract may have changed.
Environment Drift Detector
Compare environment configuration structures while keeping values masked by default.
Responsive Content Fit Lab
Resize your content and see where headings, copy, and actions start to struggle.
Webhook Delivery Simulator
See how failures, retries, and duplicate events affect webhook delivery and processing.
Capacity Cliff Simulator
Find when growing demand crosses your safe threshold and available capacity.
Retry Storm Simulator
Watch retries turn a normal traffic spike into a server-crushing storm — and see how backoff and jitter fix it.
Cache Value Simulator
Simulate cache hit rate and staleness as you change TTL, eviction policy, and traffic pattern.
Rate Limit Playground
Send a simulated stream of requests through fixed-window, sliding-window, and token-bucket limiters and watch what gets throttled.
Queue Capacity Planner
Simulate a queue under load and watch it drain or build up as arrival rate outpaces processing rate.
SLA Chain Visualizer
Chain services with their own uptime SLAs and watch how fast combined availability erodes.
Fan-Out Latency Simulator
Simulate a request fanning out to N downstream services and see how tail latency compounds.
Circuit Breaker Playground
Simulate a failing dependency and watch a circuit breaker trip open, half-open, and close.
N+1 Query Visualizer
Watch a single loop over related records explode into hundreds of database queries.
Connection Pool Simulator
Simulate concurrent requests competing for a limited database connection pool.
HTTP Cache Lab
Configure Cache-Control, ETag, and Last-Modified headers and simulate how browsers and CDNs actually cache the response.
Scope Creep Visualizer
Add "small" extra asks to a freelance project one by one and watch your effective hourly rate shrink.
AI Project Pricing Lab
Compare AI-assisted effort with the risk, review, and support you still own.
Database Decision Lab
Weigh database options against your own priorities and see a transparent, scored recommendation.
Build vs Buy
Weigh building a feature in-house against buying a third-party service, scored against your own priorities.
Tech Stack Battle
Compare candidate tech stacks head-to-head, scored against your project's actual priorities.
Distributed Systems Tax
See the real cost of splitting a system into another network hop before you decide to do it.
Monolith vs Microservices Lab
Weigh monolith vs microservices for your actual team size and deployment cadence — not dogma.
REST vs GraphQL Decision Lab
Compare REST, GraphQL, and gRPC against your API's actual shape with a transparent, weighted score.
Multi-Format Campaign Planner
Group campaign destinations into reusable master compositions and see the crop tradeoffs.
API Pagination Planner
Compare pagination behavior and explore the tradeoff between page size and request count.
Sticky Note Frame Planner
Plan how sticky notes tile inside a frame or board — to scale, before you commit to a layout.
Timeout Chain Planner
Plan timeout budgets across a chain of service calls so the whole request fails faster than the client gives up.
Frame Fit Finder
See your artwork placed inside candidate frame sizes before you buy one.
Paper Nesting Planner
Plan how multiple pieces nest onto a sheet of paper or print stock with minimal wasted area.
Project Quote Risk Planner
See which line items in a client quote carry the most risk of scope or time overrun before you send it.
Roadmap Collision Detector
Lay multiple project timelines side by side and catch where they collide before it becomes a fire drill.
Crop Guardian
Crop one image to multiple target aspect ratios at once and export every crop, right in your browser.
Drawing Grid Maker
Generate and download a proportion grid overlay for any canvas size — for tracing, scaling, or practice.
Bleed & Safe Area Builder
Generate a downloadable bleed and safe-area guide for any print size.
Value Study Maker
Turn a reference photo into a simplified tonal value study to practice shading and composition from.
Perspective Grid Maker
Generate and download a customizable 1, 2, or 3-point perspective grid for drawing practice.
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