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StatisticsCalculator, distributions, simulators
Physics SimulatorPendulum, energy, integrators
Base converterBase 2 to 64
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Atoms and chemistryPeriodic table, orbitals and valence shell
Security
Text anonymizerRedact PII and secrets (reversible)
JWT InspectorDecode JWT tokens
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Hash generatorSHA-256, SHA-384, SHA-512
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Agent file auditorCLAUDE.md, skills, MCP, hooks and permissions
Can I paste this?Secrets and cookies in a text, log or HAR before sharing it
GitHub Actions auditorCommand injection, unsafe pull_request_target, unpinned actions
Headers and CSP auditorCSP, HSTS, cookies (Secure/HttpOnly/SameSite) from a pasted curl -I
Kubernetes network reachabilityCan pod A reach pod B? NetworkPolicy, ports and broken references
MCP catalogue auditorContext cost, annotations, official registry compliance
Access LabIdentity, RBAC and governance — vendor-neutral, multi-cloud
SAML decoder and auditorSignature, expiry, audience, and the XML Signature Wrapping attack
Email headers and DMARC auditorSPF, DKIM, DMARC — from an email’s headers or its DNS records
Side-channel labAttack a secret by timing and a key by power analysis
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Defense in depthThe 7 security layers, and what Jarroba already covers with a real attack
Development & DevOps
CronGenerator and validator
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ElectronicsCircuit simulator: DC, transient, AC, MOSFETs and breadboard
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Logic GatesAND, OR, NOT and more gate simulator
Architecture SimulatorDiagram CI/CD, cloud, AI/MCP and simulate load
Quantum simulatorQubits, gates, superposition and entanglement
HammingError detection
Nginx/Apache SPA configGenerate config to serve a SPA
SemverSemantic version ranges
CORS ExplainerAnalyse your server's CORS headers
API workbenchSend requests, convert collections and compare versions
Cert inspectorAnalyse X.509 certificates in PEM format
Rate LimiterSimulate Token Bucket and Fixed Window
Assembly simulatorSimplified MIPS ISA · step-by-step · registers & memory
Operating systemsScheduling and page replacement, step by step and with sources
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Context ForgePack and shield your project for AI
Visual terminalClick and get the command: Linux, macOS, PowerShell
Project workshopSimulate your Makefile: what it rebuilds and why
Project X-rayWhat Spring will do with your code, and which dependencies are stale
Spring DoctorField injection, and the rest of the Spring Boot conventions, file by file
Test auditorOf these passing tests, which ones cannot fail?
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Artificial Intelligence
LLM costsSimulate monthly spend
Practice validityWhat still holds and what was superseded
AgentsSpec, permissions, verification and evals
Local AI cameraDetects objects and alerts, without uploading anything
Local speech transcriptionAudio to text without uploading it, and measure the error
Does this text say anything?How much you can cut without losing a single idea
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Regression & MLELeast squares, overfitting, ridge
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OCR — Image to textExtract text from images, 100% local
Finance
InflationOfficial CPI, purchasing power and savings in today's euros
Economy simulatorFirms, prices, monopolies and limited resources
Mortgage / loanPayment, real APRC of each offer and early repayment
Split expensesWho owes whom and how much
Self-employed (Spain)Social Security, IRPF, VAT and how much to set aside
Health & Wellness
BMI & healthBMI, ideal weight, BMR and sleep cycles
Productivity
PomodoroTime-block work technique
StopwatchWith laps, stages and history
Games & Entertainment
Dice3D dice from 2 to 9,999 faces, with projection
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TournamentLeagues, groups, knockouts and Swiss, with standings
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WCAG ContrastAA/AAA and the colour that does pass
Spreadsheet auditorRecalculates and compares with what's saved
Business
Meeting costHow much does each meeting really cost?
SLA / UptimeAllowed downtime, error budget and alerts
Burn rate / RunwayRunway, default alive and break-even
A/B TestAnalyse, plan and don't fool yourself by peeking
DORA MetricsYour team according to every DORA report, 2019–2025
UTM BuilderUTM links with their predicted GA4 channel
Spaces and resourcesTables, racks, beds or desks: share them out and see if they hold up
How to use
What it calculates

Estimates how long your cash will last. The burn rate is the net money you spend each month (expenses − revenue), and the runway is the number of months you survive before running out of funds.

Default alive or default dead

Paul Graham's question: if expenses stay as they are and revenue keeps growing at the rate of the last few months, do you become profitable before running out of cash? If so, you're default alive; if not, default dead, and it's better to know as early as possible. It's projected month by month, with your hires and rounds, and the minimum growth that would keep you alive is computed.

Burn rate / RunwayRunway, default alive and break-even
Runway and break-evenHow long does your cash last, will you be profitable before it runs out, and how much do you need to sell?
Your last few months'

Planned hires

Rounds or loans

Default dead: with these assumptions you run out of cash before becoming profitable.
Monthly burn rate10,000 €this month
Runway10 monthsRuns out in August 2027
First profitable monthnot reached
To survive you need to grow7.1 % per month

Cash at the end of each month; the bottom axis is months from today and the red line is zero. Hover (or tap) to read each month.