7 free tools

Free browser developer tools and code generators

Start by task

I have messy JSONValidate and format, then review fields.I have table rowsSet CSV delimiter and headers before conversion.I am debugging a URLInspect the host and query parameters.

Format JSON, convert CSV to JSON, compare text, parse URLs, test JavaScript regex, generate passwords, and export static QR codes locally.

Best for everyday development and QA jobs where you need copy-ready output, local processing, and fast checks without opening a full IDE or sending data to a backend.

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Category

Developer tools & code generators

Access

Free

Data handling note

Developer tools process pasted snippets, selected files, and generated values in the browser. Redact secrets, production tokens, cookies, and private URLs before formatting or sharing output.

Last updated

September 21, 2026

Featured tools

Best starting points in Developer tools & code generators

These tools are surfaced from the category decision guide, so they match the most common tasks before the full list below.

Format, minify, validate, repair common JSON issues, inspect tree paths, and copy JSON paths in your browser with browser-side processing.

JSON cleanup and path inspection

CSV to JSON Converter

Convert CSV data to JSON locally with delimiter choices, optional headers, nested dot-path keys, column-count diagnostics, and downloadable output.

Parse a full URL into protocol, hostname, port, path, query parameters, and fragment directly in your browser.

URL component inspection

Compare two blocks of text line by line in your browser and highlight added, removed, and unchanged lines.

Test JavaScript regular expressions locally with flags, match positions, capture groups, and highlighted results.

Pattern testing

Password Generator

Generate local random passwords with crypto randomness, symbols, length controls, ambiguous-character avoidance, and no password storage.

Local no-storage passwords

Which developer tool should I use?

Start with the data shape or publishing signal you need to inspect, format, convert, generate, or validate.

Make JSON readableJSON Formatter

Validate the source and inspect arrays, keys and units.

Next: Edit private values in your editor, then parse again.

Processing: Browser-side text processing.

Turn CSV rows into objectsCSV to JSON Converter

Set delimiter and headers; inspect duplicate names and quoted cells.

Next: Compare row counts and preserve string IDs.

Processing: Browser-side text processing.

Inspect a URLURL Parser

Read the host, path and repeated query parameters.

Next: A successful parse does not establish that a destination is safe.

Processing: Browser-side text processing.

Compare two versionsDiff Checker

Review added, removed and unchanged lines.

Next: Validate the final payload in the receiving application.

Processing: Browser-side text processing.

Test a patternRegex Tester

Check JavaScript flags, match positions and captures.

Next: Test boundaries and avoid complex patterns on long input.

Processing: Browser-side text processing.

Generate a passwordPassword Generator

Choose length and character groups.

Next: Store the result in your own password manager; do not share it in a test.

Processing: Browser-side text processing.

Make a static QR codeQR Code Generator

Select the data type and preserve a clear quiet zone.

Next: Scan the export on the intended device before printing.

Processing: Browser-side text processing.

Recommended first tool by task

Pick the route that matches the problem you are actually trying to solve.

I have messy JSONValidate and format, then review fields.I have table rowsSet CSV delimiter and headers before conversion.I am debugging a URLInspect the host and query parameters.

Common mistakes

Treating formatted data as anonymized data.
Assuming a URL parser verifies destination safety.
Losing leading zeros by converting identifiers to numbers.
Ignoring duplicate CSV headers or malformed quoted cells.

Next workflow paths

Use these when one tool is only part of the job.

Developer Data Cleanup WorkflowFormat JSON, convert CSV, inspect nested values, and prepare neutral fixtures.Clean and convert API dataUse a practical data-cleanup path before sharing samples.

Available now

All Developer tools & code generators

QR Code Generator

Generate free static QR codes for URLs, text, email, phone, Wi-Fi, and vCard content with custom colors, quiet-zone controls, and PNG/SVG export.

Instant share assets

Format, minify, validate, repair common JSON issues, inspect tree paths, and copy JSON paths in your browser with browser-side processing.

JSON cleanup and path inspection

Parse a full URL into protocol, hostname, port, path, query parameters, and fragment directly in your browser.

URL component inspection

Compare two blocks of text line by line in your browser and highlight added, removed, and unchanged lines.

Test JavaScript regular expressions locally with flags, match positions, capture groups, and highlighted results.

Pattern testing

CSV to JSON Converter

Convert CSV data to JSON locally with delimiter choices, optional headers, nested dot-path keys, column-count diagnostics, and downloadable output.

Password Generator

Generate local random passwords with crypto randomness, symbols, length controls, ambiguous-character avoidance, and no password storage.

Local no-storage passwords

Frequently asked questions

Which developer tools are available?

JSON Formatter, CSV to JSON Converter, Diff Checker, URL Parser, Regex Tester, Password Generator and QR Code Generator.

Do these tools need a backend?

The public tools process their input locally in your browser. Ordinary page requests and consented analytics are separate; see Data Handling for the boundary.

Can I convert JSON back to CSV here?

The public converter is CSV to JSON only. Use your spreadsheet application or editor for the reverse direction, and verify quoting and column types there.

Does formatting or parsing make data safe?

No. A formatter does not anonymize a payload, a URL parser does not certify a link, and a diff does not validate business rules. Review sensitive values and test the output in the receiving system.

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