SimpleToolbox

Free Online Tools — 100% Private
No Signup, No Tracking

We built 100+ free browser-based tools — calculators for finance, trading, and real estate, utilities for developers and freelancers, tools for e-commerce, health, SEO, and more — and every single one runs client-side in your browser.

No accounts · No uploads · No data collected · No downloads

100+ Tools
100% Private
0 Signups
<10ms Speed

Our Most Popular Tools

Hand-picked tools loved by thousands of professionals worldwide.

PERSONAL FINANCE

Budget Planner

Plan your monthly budget and track expenses.

Try it
PERSONAL FINANCE

ADP Paycheck Calculator

Estimate net take-home pay from hourly or salary wages.

Try it
TRADING

Prop Firm Breakeven

Calculate exactly what you need to pass your evaluation.

Try it
E-COMMERCE

Dropshipping Margin

Calculate true profit margins including ad spend and fees.

Try it
SOCIAL

Sponsorship Calc

Calculate fair brand deal rates for YouTube integrations.

Try it
SEO

UTM Builder

Generate campaign tracking URLs with proper parameters.

Try it
SEO

Keyword ROI

Calculate the actual monetary value of a ranking keyword.

Try it
PRIVACY

Bcrypt Hash Gen

Generate and verify strong bcrypt password hashes securely in your browser.

Try it
DEVELOPER

JSON Formatter

Validate and beautify JSON payloads.

Try it
DEVELOPER

Markdown to HTML

Convert Markdown to clean HTML with live preview and XSS protection.

Try it
DEVELOPER

SQL Formatter

Instantly beautify messy SQL queries with perfect indentation.

Try it
MEDIA

PDF Merger

Merge multiple PDFs locally without uploading.

Try it

Trusted by real professionals.

Don't just take our word for it. See how The Simple Toolbox is helping people work faster every day.

"I run 3 prop firm challenges simultaneously. The breakeven calculator is the only one I've found that actually accounts for trailing drawdown — and my account sizes never get uploaded to some random server."

J

James R.

Funded Futures Trader

"After the 2025 formatting tool data leak, I stopped pasting code into server-side tools entirely. This is the only JSON formatter I trust — everything runs locally and my API keys never leave my machine."

P

Priya S.

Senior Backend Engineer

"I analyze 15-20 BRRRR deals a week. BiggerPockets wants $39/month for their calculator. This one is free, faster, and my deal numbers aren't stored on someone else's platform."

M

Michael T.

Real Estate Investor

Frequently Asked Questions

Everything you need to know about the platform and how we manage your data.

No. The Simple Toolbox is 100% free and requires zero registration. We believe utility tools should be instantly accessible without friction.