I Built a Free Toolkit of 170+ Developer & Finance Tools — Here's What's Inside

Curious Noob — Tue, 17 Mar 2026 09:52:57 +0000

If you've ever had seven different browser tabs open — one for a JSON formatter, another for a Base64 encoder, a third for a regex tester, and four more for various finance calculators — this post is for you.

I built UtilsDaily.com to solve this exact problem: one fast, free, no-login place for the tools I reach for every single day.

Here's everything that's inside.

What is UtilsDaily?

UtilsDaily is a free utility platform with 170+ tools for developers, students, and finance planners. The core philosophy is simple:

Zero login required — use any tool instantly
Privacy-first — no tracking, no cookies beyond what's needed
No ads — clean interface, always
Embeddable — every tool has a free iframe embed for your blog or docs site

The tools span eight categories. Let me walk through each one.

🛠️ Developer Tools

This is where I spend most of my time. A few standouts:

JSON Formatter & Validator

→ Try it

Paste in any JSON and it'll:

Format/beautify with 2-space, 4-space, or tab indent
Minify for production (removes all whitespace)
Validate and show parse errors with clear messages
Show key count and file size

Quick tip from the docs — JSON is typically 30–50% smaller than equivalent XML, which is why it won the API format wars. The validator catches the most common mistakes: single quotes, trailing commas, and undefined values (which aren't valid JSON — use null).

SQL Formatter

→ Try it

Paste in that dense production query and get back something a human can actually read. Supports CTEs, window functions, JOINs — everything from your messy SELECT to your monstrous stored procedure.

Regex Tester

→ Try it

Live regex testing with match highlights. I use this more than I'd like to admit.

Other dev tools worth bookmarking:

Tool	What it does
UUID Generator	Cryptographically random UUID v4
Hash Generator	MD5, SHA-1, SHA-256 in the browser
JWT Decoder	Inspect header, payload, signature
Password Generator	Secure random passwords
Unix Timestamp Converter	Epoch → human-readable and back
Ruby to JSON Converter	Ruby hash syntax → valid JSON
Image to Base64	Data URI strings for CSS/HTML
CSS Box Shadow Generator	Visual builder with live preview
CSS Border Radius Generator	Rounded corners, visually
CSS Gradient Generator	Linear + radial with live preview

Formatters & Minifiers

For the days when you inherit badly formatted code:

XML Formatter — indent and validate XML
HTML Formatter — beautify HTML
YAML Formatter — format + convert YAML to JSON
CSS Formatter — readable CSS from minified soup
CSS Minifier + JS Minifier — strip whitespace for production

CSS Converters

Two I use constantly for responsive design:

PX to REM Converter — design in pixels, output in REM
PX to EM Converter — based on parent font-size
Aspect Ratio Calculator — for video embeds, image containers

🎓 Interview Preparation Guides

This section is unique — it's not just a tool, it's a deep reference.

Ruby & Rails Interview Prep (16 topics)

→ Read it

Covers everything that actually comes up in backend interviews:

Metaprogramming — define_method, method_missing, class_eval
Blocks, Procs & Lambdas — key differences with the & operator explained
Eager Loading & N+1 Queries — includes vs eager_load vs preload
Rails Design Patterns — Service Objects, Query Objects, Policy Objects, Decorators
Background Jobs — Sidekiq, SQS, Kafka compared in a decision table
SQL Fundamentals — CTEs, window functions, JOINs with runnable examples
Hotwire/Turbo — the Rails 7+ stack explained
Action Cable & WebSockets — real-time with broadcast_append_to

Each topic has actual runnable code examples, not just theory. The search bar lets you jump to any concept instantly.

Redis Interview Prep (16 topics)

→ Read it

Data types, persistence modes (RDB vs AOF), pub/sub, clustering, and caching patterns with code.

React Interview Prep (12 topics)

→ Read it

From fundamentals to senior-level concepts — hooks, reconciliation, performance patterns.

Ruby Multithreading Guide (14 topics)

→ Read it

Threads, the GIL, Mutex, Fibers, Ractor, deadlocks, and real-world concurrency patterns. Essential reading before any senior Ruby interview.

💰 Finance Tools — India

This is the largest section, built specifically for Indian users. If you're an Indian developer (like me) who also invests, you'll know the pain of switching between five different government portals just to run basic calculations.

Investment Calculators

SIP Calculator + Step-up SIP — with annually increasing contributions
Lumpsum Calculator
PPF Calculator — with tax benefits
SSY Calculator — Sukanya Samriddhi Yojana
ELSS Calculator — tax saving under 80C
CAGR Calculator + XIRR Calculator — true returns on irregular cash flows

Tax & Salary

Income Tax Calculator — Old vs New regime comparison — this one saves the most arguments
GST Calculator — inclusive and exclusive
Salary Calculator — CTC to take-home
HRA Calculator — tax exemption
EPF Calculator + VPF Calculator
Gratuity Calculator — on resignation or retirement

Loans & Comparison Tools

EMI Calculator — home, car, personal loans
Flat vs Reducing Rate Comparison — banks love quoting flat rates
Prepay vs Invest Calculator — settle the eternal debate
Buy vs Rent Calculator

Stocks & Trading

Brokerage Calculator — Equity, Intraday, and F&O charges
Capital Gains Calculator — LTCG and STCG on equity
MF Capital Gains

💵 Finance Tools — US

Three fully updated tools for 2026:

401(k) Calculator — with 2026 contribution limits and employer match
Paycheck Calculator — federal, FICA, all 50 state taxes
Mortgage Calculator — PITI with PMI, taxes, insurance
Debt Payoff Calculator — Avalanche vs Snowball strategy comparison
Self-Employment Tax Calculator — with the deductible half

✏️ Text Tools

The text manipulation tools that belong in every developer's bookmarks:

Text Diff — side-by-side comparison with highlights
Markdown Editor — live preview
Word Counter — words, chars, sentences, paragraphs
Remove Duplicates — line deduplication
Find and Replace — with regex support
Prefix & Suffix Adder — bulk line operations
Case Converter — UPPER, lower, Title, camelCase
Lorem Ipsum Generator

🎲 Converters, Health, & Random Tools

Unit Converters: Length, weight, temperature, area, speed, data storage, volume, and number base (binary/octal/decimal/hex).

Health & Fitness: BMI, body fat %, calorie needs (TDEE), macro calculator, sleep cycle calculator, pregnancy due date calculator.

Date & Time: Age calculator, timezone converter (20 cities), Pomodoro timer, business days calculator, week number calculator.

Random: Random number generator, coin flip (cryptographically secure), dice roller (D4–D20), list randomizer, random color generator.

Color: Color picker (HEX/RGB/HSL), color palette generator using color theory, gradient generator.

🔌 Embed Any Tool on Your Site

Every tool on UtilsDaily has an embed option. One line of HTML:

<iframe 
  src="https://utilsdaily.com/developers/json-formatter?embed=true" 
  width="100%" 
  height="500" 
  frameborder="0" 
  style="border: 1px solid #e2e8f0; border-radius: 8px;"
  title="JSON Formatter & Validator">
</iframe>

Attribution back to UtilsDaily is included as a small footer link — that's how the project stays free.

Why I Built It

I'm a backend engineer with experience across Ruby on Rails, Golang, and blockchain infrastructure. Over time I found myself with the same eight tabs open every day — JSON formatter, base64 tool, regex tester, EMI calculator, income tax comparison — each on a different site, each with ads, each requiring a separate bookmark.

UtilsDaily started as a personal utility page that grew into something bigger. The interview prep section came directly from my own prep work — I couldn't find a single page that covered Ruby metaprogramming, Rails design patterns, SQL fundamentals, and Redis in one place with actual runnable code examples. So I built it.

What's Coming Next

More US finance tools (Roth IRA, Social Security estimator — already live)
API documentation checker
GraphQL query formatter
Color contrast accessibility checker (WCAG)
More interview prep guides: System Design, PostgreSQL, Golang

Try It

Everything is at utilsdaily.com — no login, no ads, 170+ tools.

If there's a tool you reach for daily that's missing, drop it in the comments. I read everything and the backlog is community-driven.

Built with a focus on Developers and Finance planning (India, US), but the dev tools are universally useful. Happy to answer any questions about the tech stack or specific tools in the comments.

DEV Community: Curious Noob

I Built a Free Toolkit of 170+ Developer & Finance Tools — Here's What's Inside

What is UtilsDaily?

🛠️ Developer Tools

JSON Formatter & Validator

SQL Formatter

Regex Tester

Other dev tools worth bookmarking:

Formatters & Minifiers

CSS Converters

🎓 Interview Preparation Guides

Ruby & Rails Interview Prep (16 topics)

Redis Interview Prep (16 topics)

React Interview Prep (12 topics)

Ruby Multithreading Guide (14 topics)

💰 Finance Tools — India

Investment Calculators

Tax & Salary

Loans & Comparison Tools

Stocks & Trading

💵 Finance Tools — US

✏️ Text Tools

🎲 Converters, Health, & Random Tools

🔌 Embed Any Tool on Your Site

Why I Built It

What's Coming Next

Try It