29 free tools, zero backend

dottools.dev

Developer utilities that just work. Fast, reliable, and always available.

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Popular
{ }

JSON Formatter

Format, validate, and minify JSON data instantly

Formatters
Popular
JWT

JWT Decoder

Decode and inspect JSON Web Tokens

Encoding
Popular
B64

Base64 Encode/Decode

Encode or decode text and data in Base64 format

Encoding
ID

UUID Generator

Generate random UUIDs in bulk with one click

Generators
SSL

SSL Certificate Tools

View certificate details, build chains, convert formats

Security
Popular
.*

Regex Tester

Test regular expressions with live match highlighting

Formatters
TS

Timestamp Converter

Convert between Unix timestamps and human-readable dates

Converters
Popular
#

Hash Generator

Generate MD5, SHA-1, SHA-256, and SHA-512 hashes

Generators
***

Password Generator

Create strong, random passwords with custom rules

Generators
QR

QR Code Generator

Generate QR codes from text or URLs, download as PNG or SVG

Generators
DNS

DNS Lookup

Query DNS records across Google, Cloudflare, and NextDNS resolvers

Network
YML

YAML Lint

Validate and format YAML, convert between YAML and JSON

Formatters
Popular
%20

URL Encode/Decode

Encode or decode URLs and query strings

Encoding
CLR

Color Converter

Convert colors between HEX, RGB, and HSL formats

Converters
+/-

Text Diff Checker

Compare two texts and highlight the differences

Formatters
CRN

Cron Expression Parser

Parse and explain cron expressions in plain English

Converters
Aa

Lorem Ipsum Generator

Generate placeholder text for designs and mockups

Generators
755

chmod Calculator

Calculate Linux file permissions in numeric and symbolic notation

Converters
0x

Number Base Converter

Convert numbers between binary, octal, decimal, and hexadecimal

Converters
aA

String Case Converter

Convert text between camelCase, snake_case, kebab-case, and more

Converters
Wc

Word Counter

Count words, characters, sentences, and estimate reading time

Formatters
MD

Markdown Preview

Write Markdown and see a live rendered preview side by side

Formatters
SQL

SQL Formatter

Format and beautify SQL queries with syntax highlighting

Formatters
CSV

CSV/JSON Converter

Convert between CSV and JSON formats

Converters
&;

HTML Entity Encode/Decode

Encode or decode HTML entities and special characters

Encoding
IP

Subnet Calculator

Calculate IP subnets, network ranges, and CIDR notation

Network
OG

Open Graph Preview

Preview how your page will look when shared on social media

Formatters
BOT

Robots.txt Tester

Test if a URL path is allowed or blocked by robots.txt rules

Formatters
ZW

Invisible Character Remover

Detect and remove hidden Unicode characters from text

Formatters