DevToolsBox
Free online developer tools in one place—search below or browse by category. Each section shows a preview; open a category for the full list.
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Showing up to 10 matches. Browse categories below for the full catalog.
Conversion Tools
45 tools · showing 8
- JSON to CSV Converter Online FreeFree online JSON to CSV converter tool for exporting API data into spreadsheet-ready format.
- CSV to JSON Converter Online FreeFree online CSV to JSON converter tool to transform rows into structured JSON objects.
- XML to JSON Converter Online FreeFree online XML to JSON converter tool for transforming XML feeds into developer-friendly JSON.
- Color Converter Online Free (HEX RGB HSL)Free online color converter tool to switch between HEX, RGB, and HSL values instantly.
- JSON to XML Converter Online FreeFree online JSON to XML converter tool to generate XML payloads from JSON data quickly.
- TSV to CSV Converter OnlineFree online delimiter tool that converts tab-separated tables into comma-separated CSV files.
- CSV Delimiter Converter OnlineFree online CSV tool that swaps commas, semicolons, and tabs for locale-specific spreadsheet exports.
- YAML to JSON Converter Online FreeFree online YAML to JSON converter tool for DevOps configs and API payload conversion.
Data Tools
34 tools · showing 8
- JSON Formatter Online FreeFree online JSON formatter tool to beautify, validate, and fix JSON instantly for developers.
- JSON Minifier Online FreeFree online JSON minifier tool to compress JSON payloads and remove unnecessary whitespace.
- JSON Validator Online FreeFree online JSON validator tool to detect syntax errors and verify JSON payloads quickly.
- JSON Pretty Print OnlineFree online pretty printer that expands compact JSON into indented trees for configs and API dumps.
- XML Formatter OnlineFree online XML beautifier that adds indentation for SOAP payloads, configs, and API responses.
- XML Minifier OnlineFree online XML minifier that removes unnecessary whitespace when you need a smaller XML payload.
- CSV Validator OnlineFree online CSV checker that spots quoting issues and uneven column counts before imports fail.
- YAML Formatter OnlineFree online YAML formatter that normalizes indentation for cleaner infrastructure and app configs.
Date Tools
31 tools · showing 8
- Unix Timestamp Converter Online FreeFree online Unix timestamp converter tool to convert epoch time into human-readable dates.
- Unix Timestamp Generator Online FreeFree online Unix timestamp generator tool to get current epoch seconds and milliseconds.
- ISO 8601 to Unix Timestamp Converter OnlineFree online datetime tool that converts ISO 8601 strings into Unix epoch seconds for APIs.
- Unix Timestamp to ISO 8601 Converter OnlineFree online logging helper that prints ISO UTC strings from Unix timestamps in seconds or ms.
- Timezone Converter Online FreeFree online timezone converter tool to convert date and time across global time zones.
- Date & Time Difference Calculator OnlineFree online calculator that measures elapsed time between two datetimes in days, hours, and minutes.
- Current Time Generator OnlineFree online current time generator tool for developers to generate and create data quickly in the browser.
- Epoch Milliseconds Converter OnlineFree online epoch milliseconds converter tool for developers to convert and transform data quickly in the browser.
Developer Tools
48 tools · showing 8
- UUID Generator Online FreeFree online UUID generator tool to create random UUID v4 values for apps and databases.
- Regex Tester Online FreeFree online regex tester tool to match, debug, and validate regular expressions instantly.
- SQL Formatter Online FreeFree online SQL formatter tool to beautify queries for readability and debugging.
- SQL Validator Online FreeFree online SQL validator tool to detect syntax mistakes before executing queries.
- GUID Generator OnlineFree online GUID generator that outputs UUID-compatible strings for .NET, SQL Server, and Windows apps.
- UUID Normalizer OnlineFree online UUID normalizer that removes braces and standardizes casing for consistent comparisons.
- cURL to Fetch Converter OnlineFree online developer tool that translates curl snippets into browser fetch() calls for API prototyping.
- cURL to HTTPie Converter OnlineFree online CLI helper that rewrites curl commands into readable HTTPie syntax for API testing.
Encoding Tools
33 tools · showing 8
- Base64 Encoder Online FreeFree online Base64 encoder tool to convert plain text into Base64 strings instantly.
- Base64 Decoder Online FreeFree online Base64 decoder tool to decode Base64 text and inspect original content quickly.
- File to Base64 Encoder OnlineFree online encoder that reads small files and outputs Base64 for data URLs, tests, and API mocks.
- Base64URL Encoder Online FreeFree online Base64URL encoder tool for JWT payloads and URL-safe token generation.
- Base64URL Decoder Online FreeFree online Base64URL decoder tool to decode JWT segments and URL-safe Base64 strings.
- Image to Base64 Data URL Encoder OnlineFree online image encoder that outputs data URLs for tiny assets in HTML, CSS, or email prototypes.
- Text to ASCII Codes Converter OnlineFree online encoding inspector that lists decimal ASCII codes per character for debugging strings.
- ASCII Codes to Text Converter OnlineFree online translator that decodes space-separated ASCII numbers back into readable text.
Security Tools
37 tools · showing 8
- JWT Decoder Online FreeFree online JWT decoder tool to read token header and payload claims for developers.
- JWT Generator Online FreeFree online JWT generator tool to create test tokens for auth and API development.
- MD5 & SHA Hash Generator Online FreeFree online hash generator tool to create MD5 and SHA digests for checksums and debugging.
- Password Generator Online FreeFree online password generator tool to create strong random passwords for secure accounts.
- JWT Claims Inspector OnlineFree online helper that surfaces exp, nbf, aud, iss, and related JWT timing claims for auth debugging.
- Luhn Checksum Validator OnlineFree online Luhn validator that checks numeric identifiers for checksum validity—does not verify accounts.
- IBAN Validator OnlineFree online IBAN checker that validates format and mod-97 checksums before payment integrations.
- bcrypt Hash Generator OnlineFree online bcrypt demo that hashes passwords with a cost factor for learning—avoid real secrets here.
Text Tools
32 tools · showing 8
- Text Diff Checker Online FreeFree online text diff checker tool to compare two texts and highlight differences clearly.
- Lorem Ipsum Generator OnlineFree online lorem ipsum generator that fills layouts with placeholder paragraphs for UX mockups.
- Word & Character Counter Online FreeFree online word counter tool to count words, characters, and lines for writing tasks.
- Case Converter Online FreeFree online case converter tool to switch text between upper, lower, camel, snake, and more.
- Email Format Validator OnlineFree online email validator that tests common RFC-style syntax for signup forms and API inputs.
- Slug Generator Online FreeFree online slug generator tool to convert titles into clean SEO-friendly URL slugs.
- Text Line Sorter OnlineFree online sorter that alphabetizes newline-separated lists for configs, env files, and inventories.
- Text Reverser OnlineFree online text reverser tool for developers to process and refine data quickly in the browser.
Web Tools
40 tools · showing 8
- URL Encoder Online FreeFree online URL encoder tool to safely encode query parameters and URL path values.
- URL Decoder Online FreeFree online URL decoder tool to decode percent-encoded URLs and query strings.
- HTML Formatter Online FreeFree online HTML formatter tool to beautify markup and improve readability for developers.
- HTML Minifier Online FreeFree online HTML minifier tool to reduce page size by removing extra markup whitespace.
- CSS Minifier Online FreeFree online CSS minifier tool to compress stylesheets and improve frontend performance.
- JavaScript Minifier Online FreeFree online JavaScript minifier tool to shrink JS code for faster web loading.
- MIME Type Lookup OnlineFree online MIME detector that maps filenames and hints to Content-Type values for HTTP responses.
- HTTP Header Parser Online FreeFree online HTTP header parser tool to inspect and analyze raw request and response headers.