DevToolbox
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All tools

All tools

The full list is rendered from tool data through the shared template.

Documents / Text #1

Markdown -> MindMap

Turn Markdown headings into a simple browser-rendered mind map tree.

Documents / Text #2

Markdown -> HTML

Convert Markdown into an HTML preview and source code directly in the browser.

Documents / Text #3

Markdown -> PDF

Turn Markdown into a print-ready document and open the browser save-as-PDF flow.

Documents / Text #4

Markdown live preview

Type Markdown or load a file and preview the rendered document instantly in the browser.

Documents / Text #5

Mermaid diagram generator

Render Mermaid syntax into an SVG diagram directly in the browser.

Documents / Text #6

PlantUML renderer

Encode PlantUML source in the browser and render an SVG preview only when requested.

Documents / Text #7

JSON Viewer

Validate JSON and inspect a formatted source and navigable structure.

Documents / Text #8

YAML Viewer

Validate YAML and inspect the parsed structure plus JSON output.

Documents / Text #9

CSV Viewer

Preview CSV files as a table and inspect row and column counts.

Documents / Text #10

CSV → JSON

Validate CSV data and convert it into a JSON array.

Documents / Text #11

JSON → CSV

Convert JSON arrays or objects into escaped CSV.

Documents / Text #12

Text Diff

Compare two text blocks and highlight added, removed, and changed lines.

Documents / Text #13

Code Diff

Compare two code snippets with a whitespace-normalization option.

Documents / Text #14

Document Summary Viewer

Extract headings, key sentences, keywords, and document stats in the browser.

Documents / Text #15

HTML Preview

Render HTML in a sandboxed preview and inspect the document structure.

Documents / Text #16

TXT to PDF

Preview pasted text or a text file as a print-ready PDF document.

Documents / Text #17

Markdown Wiki Viewer

Render Markdown as a wiki-style article with outline navigation.

Documents / Text #18

RTF Viewer

Extract readable text from RTF source in the browser.

Documents / Text #19

Paragraph Formatter

Normalize loose lines and spacing into readable paragraphs.

Documents / Text #20

Case Converter

Convert text to upper, lower, title, or sentence case.

Documents / Text #21

Character Counter

Count characters, words, lines, sentences, and length without spaces.

Documents / Text #22

Text Sorter

Sort line-based text ascending, descending, or with duplicates removed.

Documents / Text #23

Line Break Cleaner

Clean unnecessary line breaks and blank lines around sentences.

Documents / Text #24

Base64 Text Encoder

Encode UTF-8 text into a Base64 string.

Documents / Text #25

Base64 Text Decoder

Decode a Base64 string into UTF-8 text.

Documents / Text #26

URL Encoder

Percent-encode URL query values or path fragments.

Documents / Text #27

URL Decoder

Decode percent-encoded URL text into a readable value.

Documents / Text #28

Slug Generator

Convert title text into a search-friendly URL slug.

Documents / Text #29

Lorem Ipsum Generator

Generate placeholder copy from selected paragraph and sentence counts.

Documents / Text #30

Memo Pad

A simple local memo pad saved in browser localStorage.

Documents / Text #31

Font Comparer

Compare the same text with two fonts and one size setting.

Documents / Text #32

OCR Result Viewer

Paste or upload OCR-extracted text to inspect lines, blocks, and suspicious characters.

Documents / Text #33

Clipboard Tool

Clean clipboard text and save pasted or clipboard images as PNG/JPG files.

Images #34

JPG to PNG

Convert JPG images to PNG.

Images #35

PNG to JPG

Convert PNG images to JPG with background color and quality options.

Images #36

WEBP Converter

Export JPG, PNG, or WEBP images as quality-controlled WEBP files.

Images #37

Image Resize

Resize an image to a chosen width and height in the browser.

Images #38

Image Compress

Reduce image file size by changing dimensions and JPG quality.

Images #39

EXIF Viewer

Read JPEG EXIF metadata in the browser and display it as a table.

Images #40

EXIF Remover

Re-export images through browser canvas to remove file metadata such as EXIF.

Images #41

Image Crop

Crop an image to a selected area and export it as PNG.

Images #42

Watermark Add

Compose a text watermark over an image in the browser.

Images #43

Sprite Sheet Generator

Combine multiple images into one downloadable sprite sheet PNG.

Images #44

Color Palette Extractor

Sample frequent colors from an image and build a palette.

Images #45

Image Rotate

Rotate an image in 90-degree steps and export it as PNG.

Images #46

Image Flip

Flip an image horizontally or vertically.

Images #47

Background Removal Mockup

A color-key mockup that makes pixels similar to the selected color transparent.

Images #48

Image Filter

Apply browser canvas filters to an image.

Images #49

Image Border

Add a custom color and width border around an image.

Images #50

Canvas Extend

Extend the canvas around an image with a colored margin.

Images #51

Image Format Info

Inspect the actual image format, dimensions, signature, alpha, and animation flags.

Images #52

Image Compare

Compare two images over the same area and visualize pixel differences.

Images #53

Placeholder Image Generator

Generate a placeholder PNG with chosen dimensions and colors.

Images #54

Profile Image Maker

Create a circular or square profile PNG from an uploaded image.

Images #55

Image Grayscale

Convert an image to grayscale PNG.

Images #56

Image Brightness

Adjust image brightness and export a PNG.

Images #57

Image Contrast

Adjust image contrast and export a PNG.

Images #58

Image Meta Tags

Generate HTML image meta tag drafts from uploaded image information.

Images #59

ICO Converter

Convert an image into a 256px ICO file.

Images #60

SVG to PNG

Render SVG markup or an SVG file to a PNG canvas.

Images #61

PNG to SVG Viewer

Embed a PNG in an SVG image tag for markup and preview inspection. This is not automatic vector tracing.

Developer tools #62

Regex Tester

Run a regular expression against test text and inspect matches and groups.

Developer tools #63

Cron Generator

Combine minute, hour, day, month, and weekday fields into a cron expression.

Developer tools #64

JSON Formatter

Validate JSON and format it for reading or minify it into one line.

Developer tools #65

SQL Formatter

Apply browser-side keyword line breaks and indentation to SQL.

Developer tools #66

Timestamp Converter

Convert Unix timestamps, milliseconds, and ISO dates to local time and UTC.

Developer tools #67

UUID Generator

Generate UUID v4 values with the browser crypto API.

Developer tools #68

JWT Decoder

Decode JWT header and payload in the browser. Signatures are not verified.

Developer tools #69

Password Generator

Generate random passwords with the browser crypto API.

Developer tools #70

HTML Formatter

A browser MVP formatter that applies line breaks and indentation around HTML tags.

Developer tools #71

CSS Formatter

Apply line breaks and indentation around CSS blocks, declarations, and semicolons.

Developer tools #72

JavaScript Formatter

A browser MVP formatter that tidies JavaScript around braces and semicolons.

Developer tools #73

XML Formatter

Apply line breaks and indentation around XML tags.

Developer tools #74

Diff Checker

Compare two texts line by line and mark added, removed, and changed lines.

Developer tools #75

Color Converter

Convert HEX, RGB, and HSL color values.

Developer tools #76

HTACCESS Generator

Generate common Apache .htaccess rewrite rule drafts.

Developer tools #77

Meta Tag Generator

Generate HTML meta tag drafts for SEO and sharing.

Developer tools #78

Robots.txt Generator

Generate robots.txt from User-agent, Allow, Disallow, and Sitemap rules.

Developer tools #79

Sitemap.xml Builder

Convert a URL list into sitemap.xml format.

Developer tools #80

HTTP Status Lookup

Look up the meaning and class of HTTP status codes.

Developer tools #81

Unicode Converter

Convert characters to Unicode code points and escape notation.

Developer tools #82

Escape / Unescape

Escape or unescape HTML, URL, and JavaScript strings.

Developer tools #83

Number Base Converter

Convert between decimal, hexadecimal, octal, and binary numbers.

Developer tools #84

QR Code Generator

Generate real QR code SVG and PNG images from text or URLs.

Video #85

MP4 to GIF

Export a local browser-playable video segment as a real GIF file.

Video #86

Video 02

Coming Soon.

Video #87

Video Compress

Try reducing size by exporting a local video as lower-resolution, lower-frame-rate WebM.

Video #88

Frame Extractor

Extract a PNG frame from a chosen time in a local video.

Video #89

Video Cutter

Export only a selected range of a local video as browser-recorded WebM.

Video #90

Video Rotate

Rotate a local video on a browser canvas and export it as WebM.

Video #91

Video Mute

Record only the local video picture to a muted WebM file.

Video #92

Video Thumbnail Generator

Generate a thumbnail image from a selected time in a local video.

Video #93

Video Resolution Resize

Redraw a local video at a chosen width and export it as WebM.

Video #94

WEBM Converter

Record any browser-playable local video through a canvas and save it as WebM.

Video #95

Video 11

Coming Soon.

Data #96

CSV Chart

Generate a bar chart from label and numeric columns in CSV data.

Data #97

Excel Viewer

Preview local Excel or CSV files as sheet tables in the browser.

Data #98

Pivot Viewer

Build a pivot table from selected row, column, and value fields in CSV data.

Data #99

Timeline Generator

Convert CSV with dates and titles into a chronological timeline SVG.

Data #100

Gantt Chart Generator

Convert task, start, and end date CSV into a simple Gantt SVG.

Data #101

Table Filter Builder

Filter a CSV table by search terms and display matching rows.

Data #102

JSON Chart Preview

Preview a simple chart from label and numeric values in a JSON array.

Data #103

CSV Statistics Summary

Detect numeric CSV columns and summarize count, sum, average, minimum, and maximum.

Data #104

Data Sampler

Extract first, last, or evenly spaced sample rows from CSV data.

Data #105

Column Mapping Tool

Reorder CSV columns into a selected output column sequence.

PDF #106

PDF Merge

Merge multiple PDF files in order.

PDF #107

PDF Split

Save selected page ranges from a PDF into a new PDF.

PDF #108

PDF Compress

Re-save a PDF in the browser and try object-stream optimization plus metadata cleanup.

PDF #109

JPG to PDF

Combine JPG or PNG images into one PDF document.

PDF #110

PDF to JPG

Render a selected PDF page to a browser canvas and save it as a JPG image.

PDF #111

PDF Rotate

Rotate every page in a PDF and save the result as a new PDF.

PDF #112

PDF Page Delete

Remove selected pages and save the remaining pages as a new PDF.

PDF #113

PDF Page Reorder

Build a new PDF from the page order you enter.

PDF #114

PDF Watermark

Add a centered text watermark to every page.

PDF #115

PDF Preview

Open a local PDF file directly inside the browser for quick review.

Network #116

Network 01

Coming Soon.

Network #117

Network 02

Coming Soon.

Network #118

Network 03

Coming Soon.

Network #119

Network 04

Coming Soon.

Network #120

HTTP Header Parser

Split pasted HTTP request or response headers into names, values, and security-related fields.

Network #121

Network 06

Coming Soon.

Network #122

Network 07

Coming Soon.

Network #123

IP Address Analyzer

Validate IPv4/IPv6 and CIDR input locally, then classify private, public, and loopback ranges.

Network #124

User-Agent Parser

Estimate browser, operating system, rendering engine, and mobile state from a User-Agent string.

Audio #125

MP3 to WAV

Save any local audio file this browser can decode as WAV.

Audio #126

WAV to MP3

Encode a local WAV file to MP3 in the browser.

Audio #127

Audio Cutter

Cut a selected range from a local audio file and save it as WAV.

Audio #128

Audio Merge

Append multiple local audio files in order and save the result as WAV.

Audio #129

Volume Adjuster

Adjust a local audio file volume in the browser and save it as WAV.

Audio #130

Audio Format Info

Inspect local audio format, duration, sample rate, channels, and peak levels.

Audio #131

Silence Remover

Remove low-level sections from local audio and save the result as WAV.

Audio #132

Audio Speed Adjuster

Change local audio playback speed in the browser and save it as WAV.

Productivity #133

Todo

Add tasks and manage completion state in browser local storage.

Productivity #134

Kanban

Manage work cards across todo, doing, and done states locally.

Productivity #135

Markdown Wiki

Save a Markdown document locally and preview it with an outline.

Productivity #136

Bookmark Manager

Save URLs, titles, and tags in browser local storage, then filter them.

Productivity #137

Habit Tracker

Track weekly habit checkmarks in browser local storage.

Productivity #138

Memo Board

Save short notes as colored cards in browser local storage.

Productivity #139

Project Notes

Save short project notes locally and export them.

Productivity #140

Focus Timer

Set focus and break lengths, then run a browser countdown.

Design / CSS #141

Favicon Generator

Generate a simple PNG favicon from text and colors in the browser.

Design / CSS #142

SVG Optimizer

Clean pasted SVG by removing scripts, event attributes, unsafe content, and optional metadata.

Design / CSS #143

CSS Box Shadow Generator

Adjust offset, blur, spread, and color to create CSS box-shadow values.

Design / CSS #144

CSS Gradient Generator

Create linear-gradient CSS from two colors and an angle.

Design / CSS #145

Flexbox Playground

Preview Flexbox layout and CSS by changing alignment options.

Design / CSS #146

CSS Grid Playground

Preview CSS Grid layout by changing columns and gap.

Design / CSS #147

Border Radius Generator

Adjust corner values to create border-radius CSS.

Archives #148

ZIP Creator

Bundle selected local files into a browser-generated ZIP download.

Archives #149

ZIP Extractor

Open a selected ZIP in the browser and download individual files.

Archives #150

Archive 03

Coming Soon.

Archives #151

Archive 04

Coming Soon.

Archives #152

TAR.GZ Viewer

Open a local TAR.GZ in the browser and inspect file names and risky paths.

Archives #153

Compression Compare

Compare raw, gzip, and deflate sizes for text input in the browser.

Archives #154

Archive Preview

Preview ZIP file names, dates, and risky paths before extracting.

Security #155

File Hash Generator

Calculate SHA hashes for a local file in the browser. Files are not uploaded.

Security #156

Hash Compare

Normalize whitespace and letter case, then compare two hash values.

Security #157

SSH Key Generator

Generate an RSA key pair with browser WebCrypto and show an OpenSSH public key plus PKCS#8 private key.

Security #158

RSA Key Generator

Generate signing-oriented RSA public/private PEM keys with browser WebCrypto.

Security #159

Checksum Viewer

Parse pasted checksum manifests into filenames, algorithms, and hash values.

Security #160

Password Strength Checker

Check password length, character mix, and repeated patterns in the browser.

Search #161

File Content Search

Find matching lines across selected local text files.

Search #162

Regex File Search

Find lines matching a regular expression across selected local text files.

Search #163

JSON Key Search

Find JSON keys or paths and show their values.

Search #164

CSV Column Search

Find matching CSV headers and preview values from those columns.

Search #165

Document Search Hub

Search text, JSON, and CSV content from one browser-only workspace.

File management #166

File Split

Split a selected local file into downloadable browser-generated parts.

File management #167

File Merge

Concatenate selected local files into one browser-generated download.

File management #168

File Browser

Filter selected local files and preview part of a text file in the browser.

File management #169

Batch File Rename

Preview new names for selected local files and copy a CSV rename plan.

File management #170

File Info Viewer

Inspect selected local file names, sizes, types, and modified dates in the browser.

Schedule #171

Calendar Viewer

Generate a month calendar and highlight today plus the selected date.

Schedule #172

Time Block Scheduler

Split a workday into focused time blocks from start/end time and block length.

Schedule #173

Recurring Schedule Generator

Generate recurring schedule dates from a start date, interval, and count.

Schedule #174

Deadline Countdown

Calculate remaining days and hours from a deadline date and time.

Log analysis #175

Nginx Log Viewer

Summarize pasted Nginx access logs by status code and request path in the browser.

Log analysis #176

Apache Log Viewer

Summarize pasted Apache combined logs by status code, client, and error request.

Log analysis #177

JSON Log Viewer

Parse JSON Lines or JSON array logs and summarize events by level.

Log analysis #178

CSV Log Analyzer

Parse CSV logs and summarize level, status, and time columns.