About CodeBySDE
Free, fast, browser-based utilities for developers, marketers and technical analysts.
74Tools
11Categories
0Sign-ups needed
FreeAlways
Our mission
Powerful development tools should not sit behind paywalls or installers. CodeBySDE provides free, instant and reliable web utilities that streamline your workflow, so you can format, convert and inspect data without switching between sites.
What we offer
API Testing
- API Test LabSend HTTP requests, inspect responses and copy the code.
Converter
- Color Converter (HEX, RGB, HSL)Convert colors between HEX, RGB and HSL with a live preview.
- CSV to JSON ConverterConvert CSV data into JSON array format instantly.
- CSV to Markdown TableTurn CSV or spreadsheet data into a Markdown table.
- Javascript Object to JSONTurn JS objects into valid JSON format online.
- Javascript Object to StringConvert JS objects to URL query strings easily.
- JSON StringifyConvert JS objects or arrays into JSON strings online.
- JSON to CSV ConverterConvert JSON data into CSV format for Excel or Sheets.
- JSON to TypeScript InterfaceGenerate TypeScript interfaces from a JSON sample.
- JSON to XML ConverterConvert structured JSON data into clean XML format.
- Markdown to HTML ConverterConvert Markdown to clean HTML.
- Number Base ConverterConvert numbers between binary, octal, decimal and hexadecimal.
- Query String to JavaScript ObjectConvert URL query strings into JavaScript objects.
- XML to JSON ConverterConvert structured XML into JSON format instantly.
Developer
- Card Number Validator (Luhn)Check a card number with the Luhn algorithm and detect its network.
- Chmod CalculatorWork out Unix file permissions in octal and symbolic form.
- CIDR and Subnet CalculatorCalculate network, broadcast and host range from a CIDR block.
- Cron Expression ExplainerExplain a cron schedule and see its next run times.
- HTTP Status Codes ReferenceLook up any HTTP status code by number or keyword.
- Regex TesterTest regular expressions and see every match and capture group.
- Unix Timestamp ConverterConvert Unix timestamps to dates and dates to timestamps.
Difference
- JSON Difference CheckerCompare and highlight differences between two JSON objects.
Encoder
- Base64 Encode and DecodeEncode text to Base64 or decode Base64 back to text.
- Hash Generator (SHA-1, SHA-256, SHA-512)Generate SHA-1, SHA-256, SHA-384 and SHA-512 hashes of text.
- HTML Entities Encode and DecodeEscape or unescape HTML special characters and entities.
- JSON String Escape and UnescapeEscape text for use inside a JSON string, or unescape it.
- JWT DecoderDecode a JSON Web Token and read its header and payload.
- Text to Binary, Hex and DecimalConvert text to binary, hex, decimal or octal and back.
- URL Encode and DecodePercent-encode or decode URLs and query string values.
Formatter
- CSS MinifierMinify CSS by removing comments and whitespace.
- JSON FormatterBeautify and validate JSON data online.
- JSON ValidatorCheck JSON and see exactly where the error is.
- XML FormatterBeautify and validate XML code effortlessly.
Generator
- CSS Gradient GeneratorCreate CSS gradients with a live preview.
- Lorem Ipsum GeneratorGenerate placeholder text by paragraphs, sentences or words.
- Password GeneratorCreate strong random passwords with the character types you choose.
- Random Number GeneratorGenerate random numbers in a range, with unique and decimal options.
- Random String GeneratorGenerate random strings, tokens and IDs of any length.
- UUID Generator (v4)Generate random version 4 UUIDs in bulk.
Marketing
- A/B Test Sample Size CalculatorWork out how many visitors each variant needs.
- A/B Test Significance CalculatorCheck whether your A/B test result is statistically significant.
- Add to Calendar Link GeneratorCreate Google, Outlook and .ics calendar links for an event.
- Break-even ROAS CalculatorFind the minimum ROAS and the maximum CPA you can afford.
- Bulk UTM Link BuilderAdd the same UTM parameters to a whole list of URLs.
- Coupon Code GeneratorGenerate unique, readable promo codes in bulk.
- Email Subject Line CheckerCheck your subject line for length and spam-style wording.
- Hashtag GeneratorTurn keywords and phrases into ready-to-use hashtags.
- Keyword Density CheckerFind the most used words and phrases in your text.
- LTV and CAC CalculatorEstimate customer lifetime value, LTV:CAC ratio and payback time.
- Mailto Link GeneratorCreate a mailto link with subject, body, CC and BCC.
- Marketing Metrics Calculator (CTR, CPC, CPA, ROAS)Calculate CTR, CPM, CPC, CPA, conversion rate, ROAS and ROI.
- Readability Checker (Flesch Score)Score how easy your text is to read.
- SERP Title and Description Length CheckerCheck title and meta description length for Google results.
- Social Media Character CounterCheck your text against X, LinkedIn, Instagram and more.
- UPI Payment Link GeneratorCreate a UPI payment link with amount and note.
SEO
- Meta Tag Generator for SEOGenerate SEO-friendly meta tags with customizable title, description, and social previews.
- Redirection CheckerCheck and trace the redirection path of any URL instantly.
Text Tool
- Email ExtractorPull every email address out of a block of text.
- Find and ReplaceFind and replace text, with regular expression support.
- HTML Tag StripperRemove HTML tags and keep the plain text.
- List Converter (Lines and Comma Separated)Convert lines to a comma separated list and back.
- Number to Words ConverterWrite numbers in words, in international or Indian format.
- Slug GeneratorTurn titles into clean, URL-friendly slugs.
- Sort and Dedupe LinesSort, reverse, deduplicate and clean up lines of text.
- Text Case ConverterConvert text to upper, lower, title, camel, snake, kebab case and more.
- Word and Character CounterCount words, characters, sentences and reading time.
URL Tool
- Domain ExtractorGet the domains and hostnames from a list of URLs.
- Punycode Converter (IDN)Convert internationalized domain names to and from Punycode.
- Tracking Parameter RemoverStrip UTM, fbclid, gclid and other tracking parameters from URLs.
- URL ExtractorPull every link out of a block of text.
- URL NormalizerStandardize URLs: lowercase host, sort parameters, remove fragments and slashes.
- Url Pro AnalyzerAnalyze, decode, and manipulate URLs like a pro.
- UTM Link BuilderBuild campaign URLs with UTM parameters for tracking.
- WhatsApp Link GeneratorCreate a wa.me click-to-chat link with a pre-filled message.
Principles
Private by design
Formatters and converters run in your browser, so your data is not uploaded. A few tools, such as the redirection checker, need our server to make the request for you, and the tool page says so.
Fast and simple
No account, no setup and no clutter. Open a tool, paste your input and copy the result.
Works anywhere
Browser-based, so it works on desktop, tablet and mobile with nothing to install.
Free
No subscriptions and no hidden fees.
About the developer
CodeBySDE is developed and maintained by Utkarsh Garg, a software engineer working across full-stack development, API design and developer tooling. The platform started as a personal collection of utilities and grew into a toolkit built around performance, usability and reliability.