Browser-local developer toolbox

Useful developer tools without uploading your data

Format payloads, inspect tokens, generate identifiers, and convert common developer data directly in your browser.

Local processingNo account requiredNo data upload

Tool directory

Choose a tool

46 utilities and growing

Format, compare, validate, convert, and query structured data without sending it to a server.

JSON

JSON Formatter Online – Format & Beautify JSON

Format, inspect, and query JSON with configurable indentation, key sorting, validation, and JSONPath selection.

Runs locally
YAML

YAML Tools Online – Format, Validate & Convert YAML

Format, validate, and convert YAML and JSON locally with YAML 1.2 parsing.

Runs locally
XML

XML Tools Online – Format, Validate & Convert XML

Format and validate XML, convert XML to JSON, or create XML from JSON entirely in your browser.

Runs locally
CSV

CSV Tools Online – Format, Validate & Convert CSV

Format and validate CSV, convert CSV to JSON, or turn JSON into spreadsheet-ready CSV locally.

Runs locally
JSON to CSV

JSON to CSV Converter Online

Convert JSON objects and arrays to CSV, flatten nested fields, and download the result locally.

Runs locally
JSON Diff

JSON Diff Online – Compare JSON Files

Compare two JSON documents and review added, removed, and changed paths.

Runs locally
JSONL

JSONL Formatter & Validator Online

Validate newline-delimited JSON, preview it as an array, normalize one record per line, or convert a JSON array to JSONL.

Runs locally
Query String

Query String Parser & Builder Online

Parse query parameters into JSON, build encoded query strings, clean and sort parameters in one pass, or run focused sorting and cleanup operations.

Runs locally
SQL

SQL Formatter & Minifier Online

Expand dense queries into readable SQL with selectable dialect and keyword casing, or compress them again.

Runs locally
JSON Repair

JSON Repair Online – Fix Invalid JSON

Repair common JSON syntax problems locally, review every change, and compare the fixed output before you use it.

Runs locally
JSON Schema Generator

JSON Schema Generator Online – Generate Schema from JSON

Generate and configure a reviewable JSON Schema from one value or multiple representative samples, including optional-field and type merging.

Runs locally
JSON Schema Validator

JSON Schema Validator Online – Validate JSON Data

Validate JSON data against a reviewable schema subset and locate contract failures without uploading either document.

Runs locally
JSON to TypeScript

JSON to TypeScript Online – Generate Interfaces from JSON

Generate exported TypeScript interfaces and type aliases from one valid JSON sample without uploading it.

Runs locally
JSON to Go

JSON to Go Struct Converter Online

Generate reviewable Go struct declarations from one valid JSON sample, including nested objects, arrays, and JSON field tags.

Runs locally
JSON Validator

JSON Validator Online – Check JSON Syntax

Check JSON syntax, locate errors, and format valid data without uploading it.

Runs locally
JSON Minifier

JSON Minifier Online – Compress JSON

Remove unnecessary whitespace and line breaks from valid JSON without uploading it.

Runs locally
JSON Tree Viewer

JSON Tree Viewer Online – Explore JSON Data

Browse nested JSON objects and arrays, expand branches, and search keys or string values without uploading data.

Runs locally
JSON Error Checker

JSON Error Checker Online – Find Syntax Errors

Find JSON syntax errors with line, column, character position, and nearby context without uploading data.

Runs locally
JSON Sort Keys

JSON Sort Keys Online – Alphabetize JSON

Sort JSON object keys alphabetically at every level while preserving values and array order.

Runs locally
JSON File Viewer

JSON File Viewer Online – Open JSON Files

Open a local JSON file, validate its contents, and view formatted data without uploading it.

Runs locally
JSON Unescape

JSON Unescape Online – Decode Escaped JSON

Decode escaped JSON strings and backslash sequences into readable text or formatted JSON without uploading data.

Runs locally
YAML Formatter

YAML Formatter Online – Format & Beautify YAML

Format YAML configuration into readable, consistently indented output without uploading it.

Runs locally
YAML Validator

YAML Validator Online – Check YAML Syntax

Check YAML syntax with a real parser and readable error feedback without uploading configuration data.

Runs locally
YAML to JSON

YAML to JSON Converter Online

Parse YAML and convert its data model to two-space JSON locally in your browser.

Runs locally
JSON to YAML

JSON to YAML Converter Online

Parse JSON and serialize the same values as readable YAML without sending the document to a backend.

Runs locally
XML Formatter

XML Formatter Online – Format & Beautify XML

Parse compact XML and rewrite it with readable indentation without sending the document to a backend.

Runs locally
XML Validator

XML Validator Online – Check XML Syntax

Check whether XML is well-formed with browser parser feedback without uploading the document.

Runs locally
XML to JSON

XML to JSON Converter Online

Parse XML and map its element structure into readable JSON with explicit attribute and text keys.

Runs locally
JSON to XML

JSON to XML Converter Online

Parse JSON and create readable XML with deterministic element, array, attribute, and text mapping rules.

Runs locally
CSV Formatter

CSV Formatter Online – Clean Up CSV

Normalize CSV quoting and record line endings while keeping table values intact.

Runs locally
CSV Validator

CSV Validator Online – Check CSV Syntax

Check CSV quoting, delimiter structure, and consistent record widths in your browser.

Runs locally
CSV to JSON

CSV to JSON Converter Online

Convert a delimited table into an array of JSON objects using its header row as keys.

Runs locally

Test regular expressions and convert text between common code-friendly naming styles locally.

Regex

Regex Tester Online – Test, Match & Replace

Test regular expressions, inspect every match, and replace text with JavaScript RegExp syntax locally.

Runs locally
Case Converter

Case Converter Online – Change Text Case

Convert text between uppercase, lowercase, sentence case, title case, camelCase, PascalCase, snake_case, CONSTANT_CASE, dot.case, kebab-case, and URL slugs locally.

Runs locally
Regex Tester

Regex Tester Online – Test JavaScript Patterns

Check whether a JavaScript regular expression matches your sample text and catch invalid pattern syntax locally.

Runs locally
Regex Matcher

Regex Matcher Online – Find All Matches

Find every regular-expression match and inspect match indexes, captures, and named groups as structured JSON.

Runs locally
Regex Replacer

Regex Replacer Online – Find & Replace Text

Preview JavaScript regular-expression replacements with capture groups and configurable flags before changing source text.

Runs locally

Encoding & Security

Encoding & Security Tools

Inspect tokens, encode text as Base64 or hex, transform URL or HTML components, and create common digests locally.

Base64

Base64 Encoder & Decoder Online

Encode UTF-8 text or hexadecimal bytes as Base64, create unpadded URL-safe Base64 (Base64URL), or decode Base64 as UTF-8 text or hexadecimal bytes locally.

Runs locally
Hex

Hex Encoder & Decoder Online

Encode UTF-8 text as hexadecimal bytes or decode hexadecimal bytes back to UTF-8 text.

Runs locally
Number Base

Number Base Converter Online – Decimal, Hex & Binary

Convert whole numbers between decimal, hexadecimal, binary, and octal without losing large integer precision.

Runs locally
HTML Entity

HTML Entity Encoder & Decoder Online

Encode HTML-sensitive characters or decode common named and numeric character references locally.

Runs locally
JWT

JWT Decoder Online

Decode JWT headers and payloads locally and inspect exp, nbf, and iat time status.

Runs locally
URL Component

URL Encoder & Decoder Online

Encode or decode a URL path, query parameter value, or fragment component, handle form-style plus-sign spaces, remove common tracking parameters, clean and sort full URLs in one pass, normalize comparable URLs, or parse a full URL.

Runs locally
Hash

Hash Generator Online – MD5 & SHA

Generate common digests from UTF-8 text or decoded Hex and Base64 bytes with browser-local processing.

Runs locally

Identifiers & Time

Identifier & Time Tools

Generate UUIDs and convert machine timestamps into readable dates with explicit UTC behavior.

Timestamp

Unix Timestamp Converter Online

Convert Unix timestamps in seconds, milliseconds, microseconds, or nanoseconds and parse ISO 8601 dates. Inputs without an offset use UTC.

Runs locally
UUID

UUID Generator & Validator Online

Generate random UUID v4 or time-ordered UUID v7 values, validate UUID versions, and inspect embedded UUID v7 timestamps locally.

Runs locally

Fresh crawl paths

Recently updated across VetaTool

Browse all updates
Guide · Updated 2026-08-26

Hashing Text vs Bytes: Encoding Pitfalls Explained

Learn why hashes depend on exact bytes, how UTF-8 encodes text, and why BOMs, Unicode normalization, line endings, hex, and Base64 cause hash mismatches.

Tool · Updated 2026-08-26

Base64 Encoder & Decoder Online

Encode UTF-8 text or hexadecimal bytes to Base64, create unpadded URL-safe Base64 (Base64URL), and decode either variant as UTF-8 text or hexadecimal bytes locally in your browser.

Tool · Updated 2026-08-26

Hash Generator Online – MD5 & SHA

Generate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 digests from UTF-8 text or decoded Hex and Base64 bytes locally in your browser.

Tool · Updated 2026-08-26

Query String Parser & Builder Online

Parse full URLs or raw query strings into JSON, build encoded queries, clean and sort parameters, remove empty, duplicate, or tracking pairs, and preserve repeated parameters with distinct values locally.

Tool · Updated 2026-08-26

URL Encoder & Decoder Online

Encode or decode URL components with encodeURIComponent-compatible percent encoding, convert application/x-www-form-urlencoded values, remove tracking parameters, clean and sort absolute URLs in one pass, normalize URLs, or parse them locally.

Tool · Updated 2026-08-26

UUID Generator & Validator Online

Generate UUID v4 or time-ordered UUID v7 batches, validate canonical UUID format and version, and decode embedded UUID v7 timestamps locally.

Troubleshooting · Updated 2026-08-26

Hash Base64 String vs Decoded Text – aGVsbG8= vs hello

Compare literal Base64 text with decoded byte hashing using the Hash input mode.

Troubleshooting · Updated 2026-08-26

Hash Hex String vs Bytes – Why 68656c6c6f Differs from hello

Compare literal hex text with decoded byte hashing using the Hash input mode.

Developer guides

Solve common data problems

Browse all guides
7 min read

How to Fix Invalid JSON Errors

Learn how to find and fix missing commas, unquoted keys, trailing commas, invalid escapes, hidden characters, and other common JSON errors.

6 min read

JSON vs JSONL: Differences and Examples

Compare JSON and JSONL structure, examples, streaming behavior, error handling, and the situations where each format is the better choice.

6 min read

Base64 vs Base64URL: What Changes?

Understand the Base64URL alphabet, padding rules, JWT usage, UTF-8 decoding, and how to convert safely between standard Base64 and URL-safe Base64.

5 min read

Unix Timestamp Seconds vs Milliseconds

Learn how to identify 10-digit and 13-digit Unix timestamps, convert between seconds and milliseconds, and avoid timezone mistakes.

7 min read

JSON Escaping Explained: Quotes, Backslashes, Newlines & Unicode

Learn how JSON escaping works for quotes, backslashes, control characters, newlines, Unicode escapes, and double-encoded JSON with practical examples.

8 min read

JavaScript Regex Cheat Sheet: Syntax, Flags & Examples

Use this JavaScript regex cheat sheet for anchors, character classes, quantifiers, groups, lookarounds, flags, and replacement syntax with examples.

7 min read

JWT Decode vs Verify: Why Decoding Is Not Verification

Learn the difference between decoding and verifying a JWT, what signature verification proves, and why issuer, audience, and time claims still need validation.

7 min read

YAML Indentation Explained: Spaces, Sequences & Mapping Errors

Learn how YAML indentation defines mappings, sequences, nested blocks, and multiline scalars, with examples for tabs, spacing, and common parser errors.

8 min read

XML Parsing and Validation Errors Explained

Understand XML parsing and well-formedness errors, how to read parser messages, and how tags, entities, attributes, namespaces, and document structure cause validation failures.

8 min read

CSV Quoting, Delimiters, and Column Rules Explained

Understand CSV quoting, comma, semicolon, and tab delimiters, consistent column counts, header rules, multiline fields, and safe CSV-to-JSON conversion.

8 min read

Query String Encoding and Repeated Parameters Explained

Understand query string percent encoding, plus signs, repeated parameters, empty values, fragments, and how JSON arrays map to repeated query keys.

9 min read

UUID Versions, Variants, and Validation Explained

Understand UUID versions 1 through 8, RFC variant bits, canonical UUID text, and what structural UUID validation can and cannot prove.

9 min read

Hashing Text vs Bytes: Encoding Pitfalls Explained

Learn why hashes depend on exact bytes, how UTF-8 encodes text, and why BOMs, Unicode normalization, line endings, hex, and Base64 cause hash mismatches.

7 min read

SQL Formatting vs Validation: What a Formatter Can and Cannot Check

Learn the difference between formatting SQL and validating it, including dialect syntax, schema checks, execution errors, query safety, and a practical review workflow.

Troubleshooting index

Debug common developer errors

Browse all troubleshooting

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