Hidden Character Detector
Invisible characters break code, logins and links. Type or paste some text to expose them.
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Image CompressorMake photos smaller in seconds, in bulk, without uploading.JSON Formatter & ValidatorMake messy JSON readable and find errors by line and column.Merge PDFJoin PDFs and images into one file, in the order you choose.Word & Character CounterLive word, character and reading-time counts with social media limits.QR Code GeneratorCreate QR codes for links, Wi-Fi, contacts and more, with your colours.Image ResizerSet a new width, height or percentage and resize many photos at once.Password GeneratorCreate strong passwords or easy-to-remember passphrases.Case ConverterSwitch text between 12 cases, from Title Case to snake_case.Compress PDFShrink scanned and photo-heavy PDFs by turning their pages into lean images.Image ConverterSwitch pictures between PNG, JPG, WebP and more, many at a time.Image CropperDrag a box, pick a ratio, and save exactly the part of the picture you want.Images to PDFCombine photos and scans into a single, tidy PDF.Regex TesterWrite a regular expression and watch it match your text as you type.Split PDFBreak a PDF into pages or ranges, or pull out just the pages you need.Base64 Encode & DecodeTurn text into Base64 and back, with full Unicode support.CSV to JSON ConverterTurn spreadsheet rows into a tidy JSON array in one paste.Find and Replace TextSwap every match in one go, from plain words to full regex patterns.JSON to CSV ConverterTurn a JSON list into a spreadsheet-ready CSV, nested fields included.PDF to ImagesTurn each PDF page into a crisp PNG or JPG image.Text Diff CheckerSee exactly what changed between two versions of a text.Unix Timestamp ConverterTurn epoch seconds into real dates, and dates into epoch time.UUID GeneratorCreate unique IDs in bulk: UUID v4, UUID v7 or ULID.Color ConverterPaste any CSS color and get it in every format, plus tints and shades.HEIC to JPG ConverterTurn iPhone HEIC photos into JPG or PNG that open anywhere.Organize PDF PagesDrag pages into order, rotate or remove them, then save a clean PDF.Random Name Picker WheelSpin a colourful wheel to pick a fair, random name from your list.Remove Duplicate LinesStrip repeated lines from a list and keep everything else in order.Sign PDFDraw, type or upload your signature and drop it onto any page of a PDF.URL Encode & DecodePercent-encode text for links and query strings, or decode it back.Percentage CalculatorFive quick percentage calculators, each with the working written out.Remove Line BreaksTurn broken, wrapped lines into clean flowing text or a single line.Contrast Checker (WCAG + APCA)Check if your text is readable, and get a fix when it is not.CSV to Excel ConverterTurn CSV files into proper Excel workbooks, one sheet per file if you like.CSV Viewer & EditorOpen a CSV as a table, fix it in place and save it back out.Excel to CSV ConverterExport any spreadsheet sheet to clean CSV without opening Excel.Hash GeneratorGet MD5 and SHA checksums of any text in one go.JWT DecoderSee what is inside a JSON Web Token and whether it has expired.QR Code ScannerDecode QR codes from images or your camera and see what is inside first.Remove Background ColorTurn a plain white (or any solid colour) background transparent.Sort LinesPut any list in order: alphabetical, numeric, by length or shuffled.Barcode GeneratorDraw barcodes in seven formats, verify the digits, download, print or batch.Markdown Editor & Live PreviewWrite Markdown with a live preview, then export clean HTML or .md.Rotate & Flip ImagesTurn, mirror and straighten a whole batch of pictures in one go.Age CalculatorExact age, total days lived and the next birthday from a date of birth.Color Palette GeneratorTurn one colour into a balanced palette and a full tint and shade scale.Fancy Text GeneratorRestyle text in 26 Unicode looks that paste anywhere, even with fixed fonts.Favicon GeneratorEvery icon size a website needs, from a picture or a couple of letters.JavaScript Beautifier & MinifierUnpack minified scripts, or compress your own and catch syntax slips.JSON to YAML ConverterTurn JSON into readable YAML for configs, pipelines and manifests.JSON Tree ViewerFold, search and explore JSON, and copy the exact path to any value.Random Number GeneratorFair random numbers in any range, from one lottery pick to thousands at once.SQL FormatterTurn a wall of SQL into a readable query, or squeeze it onto one line.SVG to PNG ConverterTurn vector SVGs into crisp PNGs at exactly the size you need.XML Formatter & ValidatorIndent, minify and validate XML without losing a single comment or CDATA block.YAML to JSON ConverterTurn YAML configs into strict JSON and see exactly where a file is broken.Add Page Numbers to PDFNumber the pages of a PDF where you want them, in the style you want.Add Watermark to ImageStamp your name or logo on photos, one at a time or a whole batch.Color Palette from ImagePull the main colours out of a photo and export them for your design.Cron Expression ExplainerRead any cron schedule in plain English and see exactly when it runs next.CSS Gradient GeneratorDesign smooth CSS gradients visually and copy code that just works.Date Difference & Working Days CalculatorDays, weeks, months and working days between two dates, with your own days off.HTML Beautifier & MinifierIndent tangled HTML so you can read it, or squeeze it down for production.HTML Entity Encode / DecodeEscape text for HTML, or turn entity codes back into readable characters.Image to Base64 ConverterGet a data URI from a picture, or the picture back from Base64 text.JSON DiffSee exactly which values changed between two JSON documents.JSON MinifierSqueeze JSON onto a single line and see how many bytes you save.JSON to TypeScript TypesGenerate typed interfaces from a JSON sample, nested objects and arrays too.Mic & Webcam TestCheck your camera, microphone and speakers before the call starts.PX to REM ConverterTurn pixels into rem, one value at a time or a whole stylesheet at once.Aspect Ratio CalculatorWork out a ratio, resize without stretching and find exact pixel sizes.CSS Beautifier & MinifierClean up a stylesheet for reading, or shrink it for shipping.CSV to Markdown TablePaste CSV or spreadsheet cells and get a tidy Markdown table back.Lorem Ipsum GeneratorNatural-looking filler text in exactly the amount your layout needs.Number Base ConverterType a number in any base and read it in all the others, however large.Photo Collage MakerArrange your photos into a clean collage for posts, stories or print.Remove Duplicate Rows from CSVFind rows that repeat in the columns that matter and keep just one.SERP & Social PreviewCheck where search results cut your title, and preview your link cards.XML to JSON ConverterTurn XML into predictable JSON, with attributes and repeats handled well.Add Text to ImageWrite on a photo, drag the text where you want it and download.CSV MergerStack many CSV exports into one file, matched column by column.CSV SplitterCut a big CSV into numbered parts that each keep the header row.JSON to SQL ConverterTurn JSON records into a ready-to-run table and INSERT statements.Password Encrypt Text & FilesLock a message or file with a password, safe to send through any channel.Printable Calendar MakerPrint a year or monthly calendar with your own dates marked on it.Slug GeneratorTurn titles into tidy, readable web addresses, one per line or in bulk.YAML ValidatorFind YAML mistakes by line and column before they break your config.Hidden Character Detector & CleanerSee the invisible characters hiding in your text, and strip them out.Gamepad & Stick Drift TesterTest every button and stick, and measure drift with real numbers.Photo Location & Metadata CheckerFind out what your photos give away before you share them, then strip it.Remove Extra SpacesTidy double spaces, ragged line ends and stray blank lines in one pass.Replace Color in ImageClick a colour in your picture and swap it for any other, shading intact.Watermark PDFStamp DRAFT, CONFIDENTIAL or your name across the pages of a PDF.Box-Shadow GeneratorBuild soft, realistic CSS shadows from layers and copy the code.Dead Pixel & Monitor TestFull-screen colours and patterns to spot bad pixels and screen flaws.Extract Emails from TextFind every email address hidden in a block of text, ready to copy.Extract URLs from TextList every link in a block of text and clean off the tracking clutter.Random Team GeneratorSplit a group into fair random teams, balanced by skill if you like.Safe Screenshot RedactorCover private details with solid boxes that cannot be un-blurred.What Is This File? IdentifierFind out what a file really is, whatever its name says.Add Border & Rounded CornersFrame pictures with a border, round the corners or crop to a circle.Chmod CalculatorTurn ticks into chmod numbers and back, with every setting explained.CSS clamp() Fluid Type CalculatorMake text and spacing grow smoothly with the screen, without media queries.CSV Data ProfilerUnderstand a new CSV in seconds: types, gaps, ranges and common values.File Checksum VerifierCheck that a download is genuine by comparing its hash, even for huge files.HTML to MarkdownTurn web page HTML into tidy Markdown for docs, notes and READMEs.PDF Copy-Paste Text FixerPaste messy PDF text, get clean paragraphs back in one step.PDF Metadata Viewer & RemoverSee what a PDF says about you, then edit or remove it before sharing.Printable Paper GeneratorDesign your own grid, dot or lined paper and print it at exact size.robots.txt Tester (incl. AI Crawlers)See which search and AI crawlers your robots.txt allows, rule by rule.Seamless Carousel SplitterCut a wide image into perfectly matching slides for a swipe carousel.Secret Splitter (Shamir)Split a secret into shares so only a group of them together can rebuild it.Subtitle Sync FixerMake subtitles line up with the video again, early, late or drifting.Cross-Stitch Pattern MakerTurn any picture into a printable stitch chart with symbols and a thread key.JSONPath TesterWrite a JSONPath query and see exactly what it matches, as you type.Keyboard TesterPress every key and watch it light up, with a ghosting and rollover check.URL Parser & Query String EditorPull a web address apart, edit its parameters and put it back together.Bulk Redirect GeneratorPaste old and new URLs, get ready-to-use redirect rules for your server.Hreflang Generator & ValidatorCreate and check hreflang tags so each visitor finds their language.JSON Escape / UnescapeMake any text safe to put inside a JSON string, and back again.Morse Code TranslatorTranslate to and from Morse code, then hear it, see it flash or save it.CSV to HTML TablePaste spreadsheet data and get a clean, accessible HTML table.Sprite Sheet Slicer & PackerCut sprite sheets into frames, or pack frames into a sheet with atlas data.Image SteganographyHide a secret message inside a picture that looks exactly the same.Text ReverserFlip text backwards by letters, words or lines, emoji and all.Add Line NumbersNumber every line of a list, script or document in one click.
12 most used toolsSee every tool on one page
Tools you will not find elsewhere
Specialist helpers for jobs most tool sites skip. Try them right here.
Keyboard Tester
Check every key before you return that keyboard. Press any key to try it.
Waiting for a key press
Printable Paper Generator
Dot grid, graph or lined paper that prints at exact size.
Design your paperPhoto Location Checker
Phone photos can carry the exact spot where they were taken. Check one of yours before you share it.
The check runs on your device. The photo is not uploaded.
Questions, answered
The short version: it is free, it is private, and it works without an account.
Is Best Online Tools really free?
Yes. Every tool is free, with no daily limit and no account. The site is paid for by a small number of clearly labelled ads.
Are my files uploaded to a server?
No. Every tool runs inside your browser, so your files and text are processed on your own device and are never sent to us.
Do I need to sign up or install anything?
No. Open a tool and use it. There is nothing to install and no account to create.
Does the site use AI?
No. Results come from plain, predictable code. The same input always gives the same output, and nothing you enter is used to train anything.
Do the tools work on a phone?
Yes. Every tool works in modern mobile browsers. Very large files depend on how much memory your device has.