Start with a task

Find the shortest useful path to an answer.

CalcSnippets pairs small browser tools with practical guides. Pick the job you are doing now, run the utility, and keep the deeper explanation close when you need it.

114local-first toolsOpen My Toolkit

Popular jobs

Useful tools for the next five minutes.

Results are generated in your browser for supported tools. Never paste secrets or private keys into a web utility.

Developer

JSON Formatter

Turn compact or difficult-to-read JSON into clean, indented JSON you can inspect and copy.

Open tool

Security

JWT Decoder

Inspect the header and payload of a JSON Web Token locally without verifying its signature.

Open tool

Security

Password Generator

Create strong random passwords with the length and character groups you choose.

Open tool

Text

Word and Character Counter

Count words, characters, lines, sentences, and reading time while you edit.

Open tool

Math

Percentage Calculator

Work out percentages, percentage change, and the original value from a percentage.

Open tool

Developer

Android SDK Command Builder

Build a reproducible Android SDK setup command set for macOS, Linux, or Windows without guessing environment variable names.

Open tool

Developer

Flutter Doctor Log Diagnoser

Paste a Flutter doctor or Gradle failure log to classify likely causes and get the next verification command.

Open tool

RAG Retrieval Evaluation Workbook

Turn a small question-and-answer sample into recall, precision, faithfulness, and citation coverage checks before changing your model.

Open tool

Choose by outcome

Four routes through the library.

Fix a developer problemJSON, regex, URLs, SQL, headers, and network helpersSee developer tools Handle data carefullyEncode, decode, hash, validate, and compare locallySee security tools Calculate a decisionTime, money, percentage, unit, and planning calculatorsSee calculators Understand the whyClear guides for debugging, content, AI, and modern workRead the archive

Fresh reading

New guides with a practical next step.

View all guides

The New AI Model Looks 30% Better. Should Your Team Migrate This Week?A practical release-day scorecard for deciding whether a new frontier model deserves production traffic, a limited trial, or a firm no.Your AI Agent Can Now Call Tools. That Does Not Mean It Is Ready for ProductionA production checklist for agent APIs covering permissions, state, retries, observability, human approval, and the failure modes hidden by demos.Stop Trusting AI Coding Benchmarks: Test the Agent on Your Repository InsteadA repeatable way to measure coding agents using real repository tasks, hidden tests, review time, security checks, and rollback-ready trials.The Longer an AI Agent Runs, the More Likely It Is to Fail QuietlyLearn why long agent runs drift, loop, and lose state, then design checkpoints, budgets, recovery, and evaluations that expose silent failure.Your AI Bill Is Rising Because Every Request Uses the Same ModelA practical model-routing strategy that balances quality, latency, privacy, and cost without turning fallback behavior into a hidden reliability risk.One Malicious Web Page Can Hijack an AI Agent: A Practical Prompt Injection DefenseUnderstand indirect prompt injection in retrieved content and browsers, then build layered controls that keep data separate from executable authority.Browser-Using AI Agents Can Click the Wrong Button Faster Than You Can NoticeA concrete safety and reliability checklist for browser agents, including domain controls, confirmation gates, state verification, and recovery.Bad Tool Schemas Turn Smart AI Agents Into Production Bug FactoriesDesign tool names, argument schemas, error responses, and authorization checks so model tool use becomes predictable and testable.