Utility portfolio lab
LaboratorU
A local-first utility factory for files, calculators, generators, widgets, and focused domain sites.
9 tools
JPG to PDFTurn JPG images into a single PDF locally in your browser.PNG to PDFTurn PNG images into a single PDF locally in your browser.PDF SplitSplit a PDF into individual page files locally in your browser.Extract Page 1Extract the first page from a PDF locally in your browser.Extract Last PageExtract the last page from a PDF locally in your browser.Remove Page 1Create a new PDF without the first page locally in your browser.Reverse PDFReverse the page order of a PDF locally in your browser.PDF MergeMerge PDF files locally in your browser without uploading documents.Rotate PDFRotate every PDF page 90 degrees clockwise locally in your browser.
4 tools
Images
5 tools
Compression
Image CompressorCompress one image locally with a browser canvas output.Gzip SizeEstimate gzip-compressed text size locally with the browser CompressionStream API.Base64 SizeEstimate Base64 expansion and decoded byte size locally.Data URLInspect MIME type, encoding, and payload size for data URLs locally.ZIP InspectorInspect ZIP metadata, compression methods, encrypted entries, and risky paths locally.
10 tools
File checks
File HashCalculate a SHA-256 hash for one file locally in your browser.File SignatureIdentify common file signatures locally from the selected file header.Hex DumpPreview the first bytes of a file as hex and ASCII locally in your browser.Checksum ManifestGenerate a SHA-256 checksum manifest for selected files locally in your browser.Checksum VerifyVerify selected files against a SHA-256 checksum manifest locally in your browser.Duplicate FilesFind duplicate selected files by SHA-256 hash locally in your browser.Large FilesRank selected files by size and flag large-file cleanup candidates locally in your browser.FAT32/exFATCheck selected file sizes and names for common FAT32/exFAT transfer issues locally.Folder ManifestGenerate a path-aware SHA-256 manifest for a selected folder locally in your browser.Folder CompareCompare a source folder and backup folder by relative path and SHA-256 hash locally in your browser.
18 tools
Developer data
JSONFormat, validate, and minify JSON locally in your browser.URL EncodeEncode or decode URL text locally without sending it anywhere.Base64Encode and decode Base64 text locally with Unicode-safe handling.CSV to JSONConvert simple CSV tables into JSON arrays locally in your browser.JSON to CSVConvert an array of JSON objects into CSV locally in your browser.JSON DiffCompare two JSON documents by parsed path locally, ignoring whitespace and key order.JSON SchemaValidate JSON against a small local JSON Schema subset for quick contract checks.JSON/YAML/TOMLConvert JSON and simple YAML/TOML mappings locally with visible subset caveats..env to JSONConvert pasted KEY=value config into JSON locally while keeping values as strings.SQLFormat common SQL snippets locally for readability without a server-side parser.JWTDecode JWT header and payload locally without verifying the signature.ColorConvert HEX and RGB colors into HEX, RGB, and HSL values locally.UTMBuild campaign URLs with UTM parameters locally.Email SignatureBuild a clean HTML email signature locally from pasted contact fields.JSON-LDGenerate common Schema.org JSON-LD blocks locally from pasted fields.Meta/OG PreviewGenerate or inspect page meta, Open Graph, and social preview tags locally.curl to CodeConvert common curl commands into fetch and Python requests snippets locally.CSS UnitsConvert CSS px, rem, and em values with a configurable base size locally.
6 tools
Text
SlugTurn titles into clean URL slugs with local text processing.Word CountCount words, characters, lines, and estimated reading time locally.CaseConvert text between uppercase, lowercase, title case, and sentence case locally.HTML EntitiesEncode or decode common HTML entities locally in your browser.Sort LinesSort lines alphabetically or reverse them locally in your browser.DeduplicateRemove repeated lines while preserving the first occurrence locally.
13 tools
Structure checks
JSON DiffCompare two JSON documents by parsed path locally, ignoring whitespace and key order.JSON SchemaValidate JSON against a small local JSON Schema subset for quick contract checks.HTML StructureCheck pasted HTML for headings, links, images, forms, and basic document structure locally.XMLFormat and validate XML locally in your browser.Markdown OutlineExtract heading structure, links, images, and list counts from Markdown locally.CSV StructureCheck CSV rows, columns, headers, and inconsistent row lengths locally.robots.txtInspect pasted robots.txt directives and common crawl-blocking signals locally.Sitemap URLsExtract URLs, lastmod values, and sitemap index references from pasted sitemap XML locally.ICS InspectInspect pasted ICS calendar text for event fields and basic structural warnings.vCard InspectInspect pasted vCard text for contact fields and basic structural warnings.Text DiffCompare two text blocks line by line locally in your browser.RegexTest JavaScript regular expressions against sample text locally.Meta/OG PreviewGenerate or inspect page meta, Open Graph, and social preview tags locally.
3 tools
Reference
7 tools
Generators
UUIDGenerate UUID v4 identifiers locally in your browser.SHA-256Generate a SHA-256 digest for text locally in your browser.Token EstimateEstimate prompt token ranges locally without model calls or billing data.ICS EventGenerate a simple calendar .ics event locally from pasted event fields.vCardGenerate a simple vCard contact locally from pasted contact fields.PasswordsGenerate strong random passwords locally with browser crypto.Lorem IpsumGenerate placeholder paragraphs locally for layouts and mockups.
2 tools
Subtitles
3 tools
Media math
3 tools
Design/vector
4 tools
Units/finance
UnitsConvert common length, area, weight, volume, temperature, and data-size units locally.PercentageCalculate percent of a value, percentage change, and what percent one number is of another locally.DiscountCalculate sale price, savings, and optional tax from price and discount values locally.MarginCalculate profit, margin, markup, and selling price from cost and price inputs locally.
4 tools
Email/DNS
SPF InspectorInspect pasted SPF TXT records locally for common syntax and policy issues.DMARC InspectorInspect pasted DMARC TXT records locally for policy, reporting, and percentage settings.DKIM HelperBuild DKIM DNS names and inspect pasted DKIM TXT or CNAME values locally.MX InspectorInspect pasted MX records locally for priority order and common record-shape issues.
6 tools
Networks/system
CIDRCalculate IPv4 network, broadcast, mask, wildcard, address count, and usable range locally.IP RangeConvert IPv4 addresses to decimal/hex and summarize inclusive IPv4 ranges as CIDR blocks locally.chmodConvert Unix permission modes and umask values into readable owner, group, and other permissions locally.Base / FloatConvert numbers across decimal, hex, binary, octal, and inspect IEEE-754 float encodings locally.CronExplain common five-field cron expressions locally without scheduling jobs or calling a provider.HeadersParse pasted User-Agent and Accept-Language headers into best-effort browser, OS, device, and language signals locally.
5 tools
Validators
LuhnValidate numbers with the Luhn checksum locally without storing or transmitting the input.IBANCheck IBAN structure, country length, and mod-97 checksum locally in your browser.VINCheck 17-character VIN shape, disallowed letters, section hints, and the 9th-position check digit locally.ISBNValidate ISBN-10 and ISBN-13 check digits locally and show the normalized identifier.EAN / UPCValidate GTIN-8, UPC-A/GTIN-12, EAN-13/GTIN-13, and GTIN-14 check digits locally.
3 tools
QR
9 tools
Date and time
Unix TimeConvert Unix timestamps and ISO dates locally in your browser.Date DurationCount calendar days and weeks between two dates locally in your browser.Add DaysAdd or subtract whole calendar days from a date locally in your browser.ISO WeekFind the ISO week-year, week number, and weekday for a date locally.WeekdaysCount weekdays and weekend days between two dates locally.Work HoursEstimate work days and work hours between dates with local weekday rules.Time DurationCalculate minutes and hours between two HH:MM times locally.ICS EventGenerate a simple calendar .ics event locally from pasted event fields.ICS InspectInspect pasted ICS calendar text for event fields and basic structural warnings.
11 tools
Calculators
PaintEstimate paint quantity with editable coverage and opening deductions.TileEstimate tile quantity with editable tile size, box coverage, and waste.ConcreteEstimate concrete volume and bag count with editable waste.MulchEstimate mulch volume and bag count from area and depth.FlooringEstimate flooring area, waste, and box count by market profile.DrywallEstimate drywall sheet counts for room walls.GravelEstimate gravel volume, bag count, and weight.WallpaperEstimate wallpaper rolls for room walls and waste allowance.RoofingEstimate roof area, squares, and bundle count with editable waste.Deck BoardsEstimate deck board rows and board count with waste allowance.LumberEstimate joists and stock boards for simple framing layouts.