DevFixPro
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25 Developer Tools: JSON, SQL, Formatter, Encoding, Hash, Regex, Password & Calculators — All Locally in Your Browser

The DevFixPro tools hub bundles 25 high-frequency developer tools — validators, formatters, converters, hash/time tools, regex and security helpers, plus performance calculators for RAM, build time and IDE tuning. 100% client-side, no API, no data uploaded, no cookies, no login. Every tool links to related fix articles on the site so when something breaks, you land on the solution.

All processing runs locally in your browser, no data uploaded.
Your input never leaves this device. Results are computed in JavaScript; no network requests, no backend, no account, no cookies. Refresh the page to auto-clear all editors.
25 tools7 categoriesLocal run · No APIFree foreverPrintable results
JSON Tools

JSON Tools

Validate, format, convert and extract JSON — link to JSON parse / SyntaxError fix articles.

JSON Validator
Validate JSON online for free — pinpoints the exact line/column of syntax errors, shows fix hints, and runs 100% locally in your browser. No signup, no data uploaded. Links to JSON parse error fix guides.
Open → devfixpro.com/tools/json-validator/
JSON Formatter
Format, beautify, indent and minify JSON online in one click. Runs 100% locally in your browser, no signup, no data uploaded. Includes JSON syntax error fixes + linked parse-error guides.
Open → devfixpro.com/tools/json-formatter/
JSON ↔ XML
Convert JSON to XML and XML back to JSON online. 100% browser-local processing, no signup, no data uploaded. Includes schema hints + links to API integration error fix guides.
Open → devfixpro.com/tools/json-xml-converter/
JSON ↔ CSV
Convert between JSON arrays and CSV online. Handles very large datasets, auto-infers headers, and runs 100% locally. No signup, no data uploaded. Links to CSV import/encoding error fixes.
Open → devfixpro.com/tools/json-csv-converter/
JSONPath Extractor
Query JSON with JSONPath expressions online — test $..field, $.array[*], filters with live match highlighting. 100% local, no signup, no data uploaded. Links to JSON parse error fix guides.
Open → devfixpro.com/tools/jsonpath-extractor/
SQL Tools

SQL Tools

Format, minify and convert SQL timestamps — link to MySQL syntax and encoding-error fix articles.

MySQL Formatter
Beautify MySQL SQL queries online with capitalization, indent and line break rules. Runs 100% locally, no signup, no data uploaded. Links to MySQL syntax error and encoding fix guides.
Open → devfixpro.com/tools/sql-formatter-mysql/
SQL Minifier
Compress SQL to single-line, remove comments and extra whitespace. Runs 100% locally in your browser. No signup, no data uploaded. Links to MySQL syntax error + encoding fix guides.
Open → devfixpro.com/tools/sql-minifier/
SQL Timestamp
Convert between MySQL DATETIME, Unix epoch seconds/milliseconds, and ISO-8601. Runs 100% locally, no signup, no data uploaded. Links to timezone/timestamp mismatch fix guides.
Open → devfixpro.com/tools/sql-timestamp-convert/
Code Formatters

Code Formatters

Format JS, TS, HTML/CSS and convert Markdown ↔ HTML — link to syntax/indent error fix articles.

JS Formatter
Format and minify JavaScript online, catch syntax errors before you build. 100% browser-local, no signup, no data uploaded. Links to JS syntax/indent error fix guides.
Open → devfixpro.com/tools/js-formatter/
TS Formatter
Beautify TypeScript and catch type-level syntax issues. Runs 100% locally in your browser. No signup, no data uploaded. Links to TS compilation/indent error fix guides.
Open → devfixpro.com/tools/ts-formatter/
HTML/CSS Beautifier
Format or minify HTML + CSS in one pane, auto-detect both. Runs 100% locally. No signup, no data uploaded. Links to HTML/CSS indent, render, and syntax-error fix guides.
Open → devfixpro.com/tools/html-css-formatter/
Markdown ↔ HTML
Convert Markdown ↔ HTML bidirectionally, GFM tables and code fences supported. Runs 100% locally, no signup, no data uploaded. Links to Markdown render and HTML parse error fix guides.
Open → devfixpro.com/tools/markdown-html-convert/
Encoding & Escaping

Encoding & Escaping

URL, Base64, UTF-8/GBK/Unicode and HTML entity conversion — link to encoding/parse-error fix articles.

URL Encode/Decode
Encode/decode URL parameters and full URLs per RFC 3986. Runs 100% locally, no signup, no data uploaded. Links to encoding / request-param-parse error fix guides.
Open → devfixpro.com/tools/url-encoder-decoder/
Base64 Encode/Decode
Encode/decode Base64 text and data URLs. Strict UTF-8 handling, no data leaves the browser. No signup, no data uploaded. Links to auth/signature/encoding error fix guides.
Open → devfixpro.com/tools/base64-encode-decode/
Charset Converter
Convert text between UTF-8, GBK raw bytes, Unicode escapes (\uXXXX) and percent-escapes. 100% local run. No signup, no data uploaded. Links to API encoding/gibberish error fix guides.
Open → devfixpro.com/tools/charset-converter-utf8-gbk-unicode/
HTML Entities
Escape <, >, &, quotes and named/numbered HTML entities, then undo it. 100% local processing. No signup, no data uploaded. Links to HTML inject / render / XSS filter fix guides.
Open → devfixpro.com/tools/html-entity-escape/
Hash & Time Tools

Hash & Time Tools

MD5/SHA hashes, UUIDs, Unix timestamp conversion — link to signature/auth/timeout fix articles.

Hash Generator
Instantly compute MD5, SHA1, SHA256, SHA512 and HMAC-SHA256 for text. All hashing runs locally in-browser with WebCrypto. No signup, no data uploaded. Links to auth/signature error fix guides.
Open → devfixpro.com/tools/hash-generator-md5-sha256/
UUID Generator
Generate 1–1000 cryptographically random UUID v4 strings at once, with uppercase/lowercase and dash toggle. 100% local run, no signup, no data uploaded. Links to PK/id collision fix guides.
Open → devfixpro.com/tools/uuid-generator/
Unix Timestamp
Convert Unix epoch seconds, milliseconds, ISO-8601 and local datetime in one pane, with UTC and your timezone rows. 100% local, no signup, no data uploaded. Links to timezone/auth timeout fix guides.
Open → devfixpro.com/tools/unix-timestamp-converter/
General Dev Tools

General Dev Tools

Regex testing, color conversion, password generation — link to regex/security/color-error fix articles.

Regex Tester
Test JavaScript RegExp live with match highlighting, named groups, split/replace/replaceAll actions, and friendly syntax error hints. 100% local. No signup, no data uploaded. Links to regex/validation error fix guides.
Open → devfixpro.com/tools/regex-tester/
Color Converter
Convert colors between HEX (#RGB/#RRGGBB/#AARRGGBB), RGB(a), HSL(a) and CSS keywords with live swatch. 100% local run, no signup, no data uploaded. Links to CSS/render color-error fix guides.
Open → devfixpro.com/tools/color-converter-hex-rgb-hsl/
Password Generator
Generate 1–200 cryptographically strong passwords with length, charset, exclude-ambiguous rules. 100% browser-local via crypto.getRandomValues. No signup, no data uploaded. Links to security/weak-password fix guides.
Open → devfixpro.com/tools/secure-password-generator/
Performance Calculators

Performance Calculators

Right-size RAM, estimate build times and tune IDE heap — hardware budgeting helpers for Low/Mid/Workstation rigs.

Dev RAM Calculator
Right-size memory for your IDE + project mix across Low/Mid/Workstation rigs. Instant, 100% browser-local, no signup, no data uploaded. Links to low-spec config and crash fix guides.
Open → devfixpro.com/tools/dev-ram-calc/
Build Time Calculator
Estimate compile/build minutes across Low/Mid/Workstation rigs and project sizes. 100% browser-local, no signup, no data uploaded. Links to slow-load optimize and export build fix guides.
Open → devfixpro.com/tools/build-time-calc/
IDE Tune Calculator
Get heap and cache budgets for VS Code, IntelliJ, Unity, Unreal and more across Low/Mid/Workstation rigs. 100% browser-local, no signup, no data uploaded. Links to mid-spec config and slow-load optimize guides.
Open → devfixpro.com/tools/ide-tune-calc/

Why local-only tools matter

  • No API keys, no signup, no rate limits.
  • Nothing leaves the browser — perfect for secrets, tokens, customer data and internal JSON payloads.
  • Every tool supports large inputs. The browser is your limit, not ours.
  • Refresh to auto-clear editors — no state persisted anywhere.
  • Friendly errors that link back to the relevant DevFixPro fix article when your input is invalid.

Integrated with the DevFixPro knowledge base

  • JSON tools auto-link to JSON parse / SyntaxError fix articles.
  • SQL tools auto-link to MySQL syntax / encoding-error fix articles.
  • Formatters auto-link to syntax / indent / compile-error fix articles.
  • Encoding tools auto-link to API encoding / param-parse error fix articles.
  • Hash/timestamp tools auto-link to signature / auth / timeout fix articles.
  • Regex / color / security tools auto-link to validation / render / security fix articles.