JSON Formatter & Validator
Format, validate, or compact JSON with useful local errors.
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Format, compare, convert, encode, and generate with focused browser-based tools built for everyday development work.
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Format common SQL statements into readable clauses.
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Development
Format code and configuration, build commands, and use practical developer references.
14 toolsWeb
Inspect and transform common values used in web development.
15 toolsText
Compare and work with plain text directly in your browser.
7 toolsData
Validate and format real-world structured identifiers.
2 toolsCrypto
Generate, hash, sign, and inspect cryptographic development values.
11 toolsConverters
Convert encodings, dates, and developer-friendly values.
16 toolsNetwork
Calculate, inspect, convert, and generate local network values.
6 toolsImages & QR Codes
Generate SVG placeholders and create or decode QR images locally.
3 toolsMath
Evaluate expressions, percentages, and progress estimates.
3 toolsMeasurement
Measure time, temperature, and benchmark performance.
3 toolsPopular now
Trending developer tools
01JSON Formatter & ValidatorFormat, validate, or compact JSON with useful local errors.02JSON to CSV ConverterConvert an array of JSON objects into downloadable CSV.03Git CheatsheetSearch and copy practical Git commands for everyday workflows.04Crontab GeneratorBuild standard five-field Unix cron expressions.05JSON MinifierValidate JSON and remove unnecessary whitespace.06SQL FormatterFormat common SQL statements into readable clauses.
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SVG Placeholder Generator
Generate a lightweight SVG placeholder with custom dimensions, colors, and text.
Images & QR CodesWiFi QR Code Generator & Decoder
Generate a WiFi connection QR code or decode an uploaded QR image and inspect its network value.
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Generate a QR code from text or a URL, or upload a QR image to read its value.
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Generate random locally assigned IPv6 Unique Local Address /48 prefixes.
NetworkMAC Address Generator
Generate random locally administered unicast MAC addresses.
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Search and copy practical Git commands for everyday workflows.
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Build standard five-field Unix cron expressions.
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Validate JSON and remove unnecessary whitespace.
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Format common SQL statements into readable clauses.
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Build numeric and symbolic Unix file permissions.
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Turn common docker run options into a Compose service.
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Why choose DevMate?
Fast results
Get useful output instantly with clear actions.
Dependable tools
Understand inputs, limits, and results.
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Core processing runs locally in your browser.
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Comfortable to use on every screen.
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Frequently asked questions
Are DevMate tools free?
Yes. Every currently available DevMate tool is free to use without creating an account.
Do you store my input or output?
No. Core tool processing happens locally in your browser, and working data is not included in analytics.
Can I use DevMate on mobile?
Yes. The catalog and all current tools are designed for desktop, tablet, and mobile screens.
Which developer tools are available?
DevMate includes JSON, text, URL, Base64, timestamp, CSV, comparison, and UUID utilities.