90 tools
Developers
JSON, CSV, XML, Base64, URL and HTML tools, minifiers, regular expressions and timestamps. Everything runs in your browser.
Tools in this category
- DevelopersQR Code GeneratorMakes a QR code from any text or link, entirely in your browser.
- DevelopersJSON FormatterIndents, sorts or minifies JSON, keeping every number exactly as you wrote it.
- DevelopersUnix Timestamp ConverterConverts between Unix time and a readable UTC date, in both directions.
- DevelopersBase64 EncoderEncodes text to Base64, handling accents and any other UTF-8 correctly.
- DevelopersRegex TesterRuns a regular expression against text and shows every match and capture group.
- DevelopersBase64 DecoderDecodes Base64 back to text, with or without padding, plain or URL-safe.
- DevelopersJSON ValidatorSays whether a JSON document is valid and, if not, exactly where it breaks.
- DevelopersURL EncoderPercent-encodes text so it can be dropped safely into a URL or a query string.
- DevelopersJSON to CSV ConverterTurns a JSON array of objects into a comma-separated table you can open in a spreadsheet.
- DevelopersURL DecoderTurns a percent-encoded link back into readable text, UTF-8 included.
- DevelopersCSV to JSON ConverterTurns a CSV table into a JSON array of objects, guessing numbers and booleans.
- DevelopersMarkdown to HTML ConverterTurns Markdown into clean HTML, with everything escaped safely first.
- DevelopersCSS MinifierStrips comments and needless whitespace from a stylesheet, safely.
- DevelopersQR Code CustomizerThe same QR code with your own colours, module size and quiet zone, as a downloadable SVG.
- DevelopersHTML EncoderEscapes the five characters that would otherwise be read as markup.
- DevelopersBarcode GeneratorCode 128 and EAN-13 barcodes as SVG, with the check digit worked out for you.
- DevelopersURL ParserBreaks a link into scheme, host, port, path, query parameters and fragment.
- DevelopersHTML DecoderTurns HTML entities back into the characters they stand for.
- DevelopersImage ResizerChange the pixel size of a picture without leaving the page — fit it in a box, cover one, or scale it by a percentage.
- DevelopersXML FormatterIndents XML so the structure is visible, or strips the whitespace back out again.
- DevelopersHTML MinifierCollapses whitespace and removes comments, leaving pre and script blocks alone.
- DevelopersImage CompressorSqueeze a photo down to a smaller file at the same pixel size, and see exactly how many bytes you saved.
- DevelopersJavaScript MinifierRemoves comments and spare whitespace from JavaScript, conservatively.
- DevelopersExcel to CSV Converter (XLSX)Turn any sheet of an Excel .xlsx workbook into a CSV file, with dates written as dates and the separator you choose, in your browser.
- DevelopersCSV to Excel Converter (XLSX)Turn a CSV or TSV file into a real Excel .xlsx workbook, with numbers stored as numbers and text kept as text, in your browser.
- DevelopersHash GeneratorThe SHA-256, SHA-512, SHA-1 or MD5 hash of any text, in hex, capitals and Base64, worked out in your browser.
- DevelopersXML ValidatorChecks that an XML document is well formed and says which tag broke it.
- DevelopersImage ConverterTurn a picture into PNG, JPEG or WebP in your browser, and see what the change does to the file size.
- DevelopersJSON to Excel Converter (XLSX)Turn a JSON list of records, such as an API response or an export, into an Excel .xlsx sheet with one column per field, in your browser.
- DevelopersText to Binary Converter (and Hex, Decimal)Turn text into the bytes a computer stores, written in binary, hexadecimal, decimal or octal, and turn bytes back into text.
- DevelopersImage to PDF ConverterPut a picture on an A4 or Letter page and save it as a PDF, with the margin and orientation you choose.
- DevelopersPNG to WebP ConverterTurn a PNG into a much smaller WebP that keeps its transparent background, in your browser, with nothing uploaded.
- DevelopersXML to JSON ConverterConvert an XML document, RSS feed, GPX track or any XML file into JSON, with attributes, repeated elements and text mapped the usual way.
- DevelopersYAML to JSON ConverterConvert YAML from Docker Compose, Kubernetes, GitHub Actions or any config file into JSON, with clear error messages that give the line number.
- DevelopersCSS Gradient GeneratorBuild a linear, radial or conic gradient and get the CSS line, with the contrast between the two ends.
- DevelopersWebP to PNG ConverterSave a WebP image as a PNG, transparency included, so it opens in any editor, document or older app.
- DevelopersImage CropperKeep a rectangle of a picture and throw the rest away, with the exact pixel numbers rather than a rough drag.
- DevelopersJPG to WebP ConverterConvert JPEG photos to WebP, usually 25 to 35 % smaller at the same visual quality, in your browser.
- DevelopersJSON to YAML ConverterConvert JSON into clean, readable YAML for Kubernetes, Docker Compose, GitHub Actions or any configuration file.
- DevelopersPassphrase GeneratorA password made of random common words, with the exact entropy stated so you can judge it rather than trust it.
- DevelopersSVG to PNG ConverterTurn an SVG drawing into a PNG at 1×, 2×, 4× or 8× its size, keeping the transparent background, in your browser.
- DevelopersBox Shadow GeneratorBuild a CSS box shadow or text shadow from the offsets, blur, spread and colour, and see how much room it needs.
- DevelopersPNG to ICO Converter (Favicon Maker)Turn a PNG, JPG, WebP or SVG into a .ico file with several sizes inside, ready to use as a favicon or a Windows icon.
- DevelopersPNG to JPG ConverterSave a PNG as a JPEG at the quality you choose, and see how many bytes that costs or saves.
- DevelopersRandom Token GeneratorRandom strings in hex, Base58, Base64 or digits, with the exact number of bits of entropy they carry.
- DevelopersURL Slug GeneratorTurn titles into clean, readable web addresses: lowercase, accents removed, words joined by hyphens, one slug per line.
- DevelopersVideo Bitrate CalculatorBitrate from resolution, frame rate and bits per pixel, with the file size, the raw uncompressed rate and the compression ratio.
- DevelopersScreen Resolution CheckerThe size of the screen you are on, in the pixels pages are told about and in the pixels the panel really has.
- DevelopersBase64 to Image ConverterPaste Base64 text or a data URI and see the picture, find out what kind of file it really is, and save it with the right extension.
- DevelopersBorder Radius GeneratorSet four corners and get the shortest CSS that produces them, with a warning when the box is too small to hold them.
- DevelopersImage to Base64 Converter (Data URI)Turn an image into Base64 text you can paste straight into HTML, CSS or JSON, as a data URI, an <img> tag or a CSS background.
- DevelopersJPG to PNG ConverterSave a JPEG photograph as a PNG file, in your browser, without sending it anywhere.
- DevelopersHTML PreviewPaste HTML and see it drawn straight away, with a count of the elements and a list of any tags left open.
- DevelopersAudio File Size CalculatorHow much space uncompressed audio takes, from the sample rate, bit depth, channels and length — and how much a compressed version would take.
- DevelopersBrowser CheckerWhat browser you are using, which version, which engine and which system — read from the line your browser announces.
- DevelopersSRT to VTT Converter (Subtitles)Convert SubRip (.srt) subtitles into WebVTT (.vtt) for HTML5 video and most web players, with an optional time shift.
- DevelopersStreaming Bandwidth CalculatorPeak bandwidth for a number of concurrent viewers, and the monthly data transfer and cost that follow from it.
- DevelopersWebP to JPG ConverterTurn a WebP picture into an ordinary JPEG that any program will open.
- DevelopersVTT to SRT Converter (Subtitles)Convert WebVTT (.vtt) subtitles into SubRip (.srt) for VLC, video editors, TVs and media players, with an optional time shift.
- DevelopersDevice CheckerWhat your browser is willing to say about the machine underneath: platform, processor cores, memory and touch.
- DevelopersAudio Latency CalculatorBuffer latency in milliseconds, round-trip delay, and the distance you would have to stand back to feel the same thing.
- DevelopersPX to REM Converter (CSS Units)Convert a CSS pixel size to rem, em, points, percent and viewport units, for any root font size.
- DevelopersColour Depth CalculatorLevels per channel, total colours, raw bitrate and the size of one banding step, for any bit depth.
- DevelopersFFT Resolution CalculatorFrequency bin width, window length, usable bins and hop size, from the sample rate and the FFT size.
- DevelopersChroma Subsampling CalculatorData rate and frame size for 4:4:4, 4:2:2, 4:2:0 and 4:1:1, with the chroma resolution and what each one saves.
- DevelopersEthernet Goodput Calculator (Real Throughput and Frames per Second)The real data rate you can expect on an Ethernet link once preamble, headers, checksum, inter-frame gap and IP/TCP headers are paid for, and how many frames per second the line carries.
- DevelopersPixel Density (PPI) CalculatorPixels per inch of a screen from its resolution and diagonal, the size of each pixel, and the viewing distance beyond which individual pixels disappear.
- DevelopersSLA Uptime and Downtime CalculatorHow much downtime an availability target such as 99.9 % allows per year, month, week and day.
- DevelopersGOP and Keyframe Interval CalculatorGOP duration in seconds, keyframes per minute, the I, P and B counts inside a GOP, and whether it lines up with the segment length.
- DevelopersAmdahl's Law Calculator (Parallel Speed-up Limit)Speed-up of a program on n processors from the share that can run in parallel, the ceiling it can never pass, and how efficiently the cores are used.
- DevelopersBloom Filter Calculator (Size, Hash Functions, False-Positive Rate)How many bits, how much memory and how many hash functions a Bloom filter needs to hold a number of items at a false-positive rate you accept.
- DevelopersCCTV Storage Calculator (NVR / DVR)How many terabytes a video surveillance recorder needs for a number of cameras, a bitrate and a retention period.
- DevelopersCOCOMO Software Effort Estimator (Basic COCOMO)Effort in person-months, development time, average team size, productivity and cost of a software project from its size in thousands of lines of code, using Boehm's Basic COCOMO.
- DevelopersFloating-Point Precision Calculator (IEEE 754 Float, Double, Half, bfloat16)How coarse the number line is around any value in half, bfloat16, single or double precision: the gap to the next number, machine epsilon, reliable digits and the largest integer that is still exact.
- DevelopersHalstead Complexity Metrics Calculator (Volume, Difficulty, Effort)Halstead volume, difficulty, effort, estimated writing time and delivered bugs of a program from its counts of operators and operands.
- DevelopersMaintainability Index Calculator (Halstead, Cyclomatic Complexity, Lines of Code)The maintainability index of a function, class or file from its Halstead volume, cyclomatic complexity and lines of code, on the original scale and on the 0–100 scale used by Visual Studio.
- DevelopersRAID Capacity CalculatorUsable space, storage efficiency and how many disks can fail for RAID 0, 1, 5, 6 and 10, with the capacity your computer will actually report.
- DevelopersRAID IOPS Calculator (Write Penalty)Random IOPS an array can sustain for a given mix of reads and writes, after the RAID write penalty, and the throughput that represents.
- DevelopersTCP Throughput Calculator (Mathis Formula: Loss and Round-Trip Time)The most one standard TCP connection can carry for a given round-trip time, segment size and packet loss rate — and the loss rate you would need for a target speed.
- DevelopersTimer and PWM Frequency Calculator (Prescaler, TOP and Resolution for Arduino, AVR, STM32)PWM or overflow frequency from the timer clock, prescaler and counter top value, with the period, the duty-cycle resolution and the TOP you would need for a wanted frequency.
- DevelopersUniversal Scalability Law Calculator (Gunther, Amdahl and Beyond)Relative capacity and throughput of a system with N processors or nodes, from its contention and coherency coefficients, with the number of nodes at which adding more starts to hurt.
- DevelopersVoIP Bandwidth Calculator (Codec, Packet Size and Headers)Real network bandwidth of a voice call from the codec bit rate, packet interval, IP version and link layer, and the total for several calls — in each direction.
- DevelopersFibre Latency Calculator (Minimum Ping by Distance)The physical minimum round-trip time over an optical fibre route, from its length, compared with light in vacuum.
- DevelopersCache Latency Calculator (Average Memory Access Time)Average access time of a cache or any fast-store-in-front-of-a-slow-one from the hit rate, hit time and miss penalty, and the speed-up it gives.
- DevelopersError Budget and Burn Rate Calculator (SLO)Error budget, burn rate and time until the budget runs out, from an SLO, the error rate you are seeing and the SLO window.
- DevelopersHash Table Load Factor Calculator (Expected Probes: Linear Probing, Double Hashing, Chaining)The load factor of a hash table and the average number of probes a lookup needs — for linear probing, double hashing and chaining — plus the table size that keeps you under a chosen load.
- DevelopersBandwidth-Delay Product Calculator (TCP Window)How much data must be in flight to fill a network link, and the throughput a single TCP connection can reach with a given window size.
- DevelopersID Collision Probability Calculator (UUID, Random Tokens)Chance that two randomly generated identifiers — UUIDs, tokens, short codes — come out the same, and how many you can make before that becomes likely.
- DevelopersGustafson's Law Calculator (Scaled Speedup)Speedup when the problem grows with the number of processors, by Gustafson's law, set beside Amdahl's fixed-size speedup.
- DevelopersPUE Calculator (Data Centre Energy Efficiency)Power usage effectiveness and DCiE of a data centre or server room, with how much power and energy go to cooling and losses instead of computing.