Free Online Tools
for Everyone
Format, convert, calculate — all in your browser. No installs. No accounts.
How it works
Every Stax tool follows the same pattern — open, use, done.
Pick a tool
Browse 235+ free tools by category or search by name. No account, no paywall.
Works in your browser
Every tool runs 100% client-side. Your files and data never leave your device.
Done instantly
Results in seconds. Copy, download, or share — no waiting, no email, no limits.
Why Stax?
Built for speed, privacy, and everyone — no exceptions.
Privacy by design
Tool logic runs in your browser. Your files, data, and inputs never reach our servers.
Instant results
No server round-trip. Processing happens locally — output is immediate.
7 languages
Every tool page localized in EN, HI, ES, FR, AR, JA, and TH.
Works everywhere
Fully responsive on desktop, tablet, and mobile. No app install required.
235+ tools, one place
Developer, finance, PDF, image, health, engineering — stop Googling a new tool for every task.
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All Tools
Browse by category or search above.
Developer Tools
69 tools
JSON, regex, encoding, hashing, color, CSS, and more
Finance Calculators
50 tools
EMI, SIP, tax, salary, GST, PPF, NPS, and more
AI Writing
7 tools
Humanize, paraphrase, detect, summarize, generate
4 tools
Link generator, QR code, message formatter
PDF Tools
12 tools
Compress, merge, convert PDF files
Image Tools
9 tools
Resize, compress, convert formats, all in-browser
Health
18 tools
BMI, calorie, and other personal health calculators
Creator Tools
9 tools
YouTube thumbnail, earnings calculator, more
Career & Business
7 tools
Resume builder, invoice generator, email signatures
SEO & Marketing
6 tools
UTM builder, schema markup, meta preview, robots.txt, sitemap
Embedded / Electronics
14 tools
Resistor codes, Ohm's law, 555 timer, IEEE 754, pinouts
Civil Engineering
15 tools
Beam, concrete, rebar, brick, staircase, and area calculators
Mobile Dev
5 tools
App icons, deep links, PWA manifest, screen sizes
AI & Prompt Tools
4 tools
Prompt builder, token counter, system prompt & image prompt generators
Workplace Safety & WHS
8 tools
Noise, manual handling, fall clearance, heat stress, LTIFR, and risk calculators
From the Blog
Tips, guides and updates from the Stax team.
Diff Checker: What It Is, How It Works, and 6 Use Cases Beyond Code Review
A side-by-side comparison of diff algorithms, how unified and split diff formats work, why character-level diffs matter for text editing, and practical use cases for diff checkers outside of version control.
EPF vs NPS vs PPF: The Three-Way Retirement Comparison for Salaried Indians
Step-by-step comparison of EPF, NPS, and PPF — contributions, interest rates, lock-in, withdrawal rules, tax treatment at maturity, and how to combine all three for a robust retirement plan.
UTF-8, Unicode, and Character Encoding: What Every Developer Needs to Know
Why mojibake happens, how Unicode code points map to UTF-8 bytes, the difference between ASCII, Unicode, and UTF-8, and why 'just use UTF-8 everywhere' is correct advice but still requires understanding.
TDS on Rent Above ₹50,000: What Tenants Must Do Before the Deadline
Most tenants believe TDS on rent is the landlord's problem. It isn't. If you pay monthly rent above ₹50,000, the obligation to deduct, deposit, and file falls entirely on you — and the penalties for non-compliance are steep.
Frequently Asked Questions
Everything you need to know about Stax Tools.
Yes. Every tool on Stax is completely free to use with no hidden fees, trials, or paywalls. There is no premium tier — all features are available to everyone.
No account or sign-up is required. Just open any tool and start using it immediately. Stax is designed to be friction-free.
Yes. All processing happens entirely in your browser using JavaScript — your files, text, and inputs are never uploaded to any server. Stax does not log or store your input data.
Stax Tools works in all modern browsers including Chrome, Firefox, Safari, Edge, and Brave. No plugins or extensions are required.
Yes. All Stax Tools are fully responsive and work on smartphones and tablets. Most tools are optimized for touch input as well as desktop.
Stax covers developer tools (JSON formatter, regex tester, base64 encoder), PDF tools (compressor, merger, splitter), image tools (resizer, converter, color picker), finance calculators (EMI, SIP, BMI), text & writing tools, engineering calculators, and more.
Stax Tools is available in 7 languages: English, Hindi, Spanish, French, Arabic, Japanese, and Thai. Each tool page includes localized FAQ and SEO content.
New tools are added regularly. You can follow updates via the blog at stax.tools/blog or subscribe to the RSS feed at stax.tools/feed.xml.
Social Media
6 tools
Instagram fonts, hashtag generators, image resizer