Online Toolbox
A collection of handy tools that run entirely in your browser — no login needed. All computation happens on your device; your data never leaves it.
Common scenarios
Recently used
Unit Converter
Pick a category, then the from/to units; leave "to" empty to output every unit in that category.
Math Calculator
Safely evaluate math expressions with functions and constants. Example: 2*(3+5)/sin(pi/4)
QR Code Generator
Generate a QR code from text or a URL. Short text is instant; over-capacity input gives an exact hint. PNG bitmap / SVG vector supported.
Image ↔ Base64
Upload an image to convert to Base64, or paste Base64 to preview the image.
Image Editor
Client-side image editing: free crop, rotate / deskew, swap solid-color background, restore the original at any time, export at a chosen format / file size / DPI. Images never leave your browser.
Image Resizer
Change image resolution (width × height), optionally locked to the original aspect ratio.
Image Compressor
Compress images by reducing quality or resolution, with a live compression ratio.
Image Format Converter
Convert between PNG / JPEG / WebP / BMP / ICO (browsers cannot export AVIF, GIF, TIFF).
Text
Text Editor
Character replace, case conversion, text reversal and other basic editing operations.
Text Diff
Line-by-line LCS diff: red for deleted, green for added, orange for modified; inline character-level diff; summary on top.
Markdown
Check Markdown for skipped heading levels, unclosed code fences and ragged tables; tidy the layout and preview it rendered.
Regular Expression
Regex matching with common pattern templates (phone / email / ID…); every match position is highlighted.
Structured Data
JSON
Format, minify, expand, validate, explore as a collapsible tree (copy path + search nodes + JSONPath query), generate TS interfaces / Java POJOs, build JSON samples from POJOs, diff two documents, and convert to XML / CSV / YAML / Properties / TOML.
XML
Format (pretty-print) and minify XML; browse it in a collapsible tree view (search + filter + path copy); convert to JSON / CSV / YAML / Properties / TOML.
CSV
Parse and preview CSV as a table (sort and filter right from the header); convert to JSON / XML / YAML / Properties / TOML.
YAML
Parse and format YAML (indent 2/4); browse it in a tree view (search + filter + path copy); convert to JSON / XML / CSV / Properties.
Properties
Parse Java .properties files; tree view (dotted keys restored to a hierarchy, with search, filter and path copy); convert to JSON / XML / YAML / CSV / TOML.
TOML
Parse and validate TOML with errors pinned to the exact line; also tidy it up, browse it in a tree view (search + filter + path copy), or convert it to JSON / YAML / XML / CSV / Properties.
Encoding & Security
Base64 Encode/Decode
Base64 encode/decode, plus Base32 encode/decode.
URL Encode/Decode
Percent encoding / decoding for URLs, plus component-level encoding.
Base Converter
Convert between binary / octal / decimal / hexadecimal, or encode text (UTF-8 bytes) into any base.
Hash & Digest
MD5 / SHA-1 / SHA-256 / HmacSHA256 / SM3 digests.
Symmetric Encryption
AES / SM4 / DES / 3DES symmetric encryption & decryption.
Asymmetric Encryption
SM2 / RSA asymmetric encryption & decryption, with one-click key pair generation.
Network
My IP Address
Show the public IP address of your current network (the NAT egress IP).
IP Lookup
Look up an IP address: country, region, city, ISP and coordinates (free public APIs).
DNS Lookup
Query A / AAAA / CNAME / MX / TXT / NS records; you can paste a full URL.
HTTP Request
Send GET / POST / PUT / DELETE requests with custom headers and body, then inspect the response. When a call fails it tells you whether it is a network, CORS or API problem — with actionable fixes.
Time
Current Time
Show your current local time with Unix timestamp / ISO 8601 / UTC.
Timestamp Converter
Convert between Unix timestamp and human-readable date.
Date Calculator
Days / hours / minutes / seconds between two dates; add or subtract days / months / years.
Time Zone Converter
Convert the same moment between time zones.
Solar / Lunar Calendar
Convert between Gregorian and Chinese lunar dates (1900-2100).
Timer
Stopwatch / countdown.
Developer Tools
JWT Parser
Decode the JWT header and payload, show issued / expiry times; decoding only, no signature verification.
Cron Expression
Build a cron expression visually, or validate one: explains each field in plain words, points out exactly which field is wrong, and lists the next run times. Supports K8s 5-field and Spring 6-field styles.
SQL Formatter
Beautify / format SQL for many dialects, minify it to one line, and catch missing brackets, unpaired quotes and other common mistakes.
Image
Image Format Converter
Convert between PNG / JPEG / WebP / BMP / ICO (browsers cannot export AVIF, GIF, TIFF).
Image Compressor
Compress images by reducing quality or resolution, with a live compression ratio.
Image Resizer
Change image resolution (width × height), optionally locked to the original aspect ratio.
Image Editor
Client-side image editing: free crop, rotate / deskew, swap solid-color background, restore the original at any time, export at a chosen format / file size / DPI. Images never leave your browser.
Image ↔ Base64
Upload an image to convert to Base64, or paste Base64 to preview the image.
QR Code Generator
Generate a QR code from text or a URL. Short text is instant; over-capacity input gives an exact hint. PNG bitmap / SVG vector supported.