"); lines.push(' '); lines.push(' '); lines.push(" Generated Test Data Report"); lines.push(" "); lines.push(""); lines.push(""); lines.push("

Employee Data Report

"); lines.push("

Generated on: 2026-06-13 | Total records shown below

"); lines.push(" "); lines.push(" "); lines.push(" "); lines.push(" "); lines.push(" "); var idx = 1; var currentLen = lines.join("\n").length; while (currentLen < sizeInBytes - 300 && idx < 999999) { var rec = generateRecord(idx, rand); var badgeClass = rec.isActive ? "active" : (rec.status === "pending" ? "pending" : "inactive"); var row = ' '; currentLen += row.length + 1; if (currentLen > sizeInBytes - 100) break; lines.push(row); idx++; } lines.push(" "); lines.push("
IDNameEmailDepartmentJob TitleSalaryStatusLocation
' + rec.id + '' + rec.firstName + ' ' + rec.lastName + '' + rec.email + '' + rec.department + '' + rec.jobTitle + '$' + rec.salary.toLocaleString() + '' + rec.status + '' + rec.city + ', ' + rec.state + '
"); lines.push("

Report contains " + (idx - 1) + " records.

"); lines.push(""); lines.push(""); return padToSize(new TextEncoder().encode(lines.join("\n")), sizeInBytes); } // --- SQL: valid CREATE TABLE + INSERT statements --- function generateSQL(sizeInBytes) { var rand = rng(42); var lines = []; lines.push("-- Auto-generated SQL test data"); lines.push("-- Generated: 2026-06-13"); lines.push(""); lines.push("CREATE TABLE IF NOT EXISTS employees ("); lines.push(" id INT PRIMARY KEY AUTO_INCREMENT,"); lines.push(" uuid VARCHAR(36) NOT NULL UNIQUE,"); lines.push(" first_name VARCHAR(50) NOT NULL,"); lines.push(" last_name VARCHAR(50) NOT NULL,"); lines.push(" email VARCHAR(100) NOT NULL UNIQUE,"); lines.push(" phone VARCHAR(20),"); lines.push(" age INT,"); lines.push(" job_title VARCHAR(100),"); lines.push(" department VARCHAR(50),"); lines.push(" salary DECIMAL(10,2),"); lines.push(" status VARCHAR(20) DEFAULT 'active',"); lines.push(" city VARCHAR(50),"); lines.push(" state VARCHAR(10),"); lines.push(" ip_address VARCHAR(15),"); lines.push(" join_date DATE,"); lines.push(" is_active BOOLEAN DEFAULT TRUE,"); lines.push(" created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP"); lines.push(");"); lines.push(""); lines.push("INSERT INTO employees (id, uuid, first_name, last_name, email, phone, age, job_title, department, salary, status, city, state, ip_address, join_date, is_active) VALUES"); var idx = 1; var currentLen = lines.join("\n").length; var valueLines = []; while (currentLen < sizeInBytes - 100 && idx < 999999) { var rec = generateRecord(idx, rand); var val = "(" + rec.id + ", '" + rec.uuid + "', '" + rec.firstName + "', '" + rec.lastName + "', '" + rec.email + "', '" + rec.phone + "', " + rec.age + ", '" + rec.jobTitle + "', '" + rec.department + "', " + rec.salary + ".00, '" + rec.status + "', '" + rec.city + "', '" + rec.state + "', '" + rec.ip + "', '" + rec.joinDate + "', " + (rec.isActive ? "TRUE" : "FALSE") + ")"; currentLen += val.length + 2; if (currentLen > sizeInBytes - 20) break; lines.push(shape); idx++; } lines.push(""); return padToSize(new TextEncoder().encode(lines.join("\n")), sizeInBytes); } // --- Galois Field mathematics for O(log N) CRC-32 combination --- var POLY = 0xedb88320; function multmodp(a, b) { if (a === 0 || b === 0) return 0; var m = 0x80000000; var p = 0; for (;;) { if (a & m) { p ^= b; if ((a & (m - 1)) === 0) break; } m = m >>> 1; b = (b & 1) ? ((b >>> 1) ^ POLY) : (b >>> 1); } return p >>> 0; } var x2n_table = []; (function init_x2n_table() { var p = 0x40000000; x2n_table[0] = p >>> 0; for (var n = 1; n < 32; n++) { p = multmodp(p, p); x2n_table[n] = p >>> 0; } })(); function x2nmodp(n, k) { var p = 0x80000000; while (n > 0) { if (n % 2 !== 0) { p = multmodp(x2n_table[k & 31], p); } n = Math.floor(n / 2); k++; } return p >>> 0; } function crc32_combine(crc1, crc2, len2) { return (multmodp(x2nmodp(len2, 3), crc1) ^ crc2) >>> 0; } function crcOfSpaces(len) { if (len === 0) return 0; if (len === 1) return 0xe96ccf45; // CRC of a single space byte [32] var half = Math.floor(len / 2); var halfCrc = crcOfSpaces(half); var combined = crc32_combine(halfCrc, halfCrc, half); if (len % 2 !== 0) { combined = crc32_combine(combined, 0xe96ccf45, 1); } return combined; } // --- Dynamic zip internal padding --- function padZipInternal(data, targetSize, paddingParts) { var len = data.length; var eocdPos = -1; for (var i = len - 22; i >= 0; i--) { if (data[i] === 0x50 && data[i+1] === 0x4B && data[i+2] === 0x05 && data[i+3] === 0x06) { eocdPos = i; break; } } if (eocdPos === -1) { return [data]; } var view = new DataView(data.buffer, data.byteOffset, data.byteLength); var cdSize = view.getUint32(eocdPos + 12, true); var cdStartOffset = view.getUint32(eocdPos + 16, true); var numRecords = view.getUint16(eocdPos + 8, true); var P = targetSize - data.length - 98; if (P <= 0) { return [data]; } var paddingCrc = crcOfSpaces(P); // Construct LFH of padding.txt var lfh = new Uint8Array(41); var lfhView = new DataView(lfh.buffer); lfh.set([80, 75, 3, 4], 0); lfhView.setUint16(4, 10, true); lfhView.setUint16(6, 0, true); lfhView.setUint16(8, 0, true); lfhView.setUint16(10, 0, true); lfhView.setUint16(12, 0, true); lfhView.setUint32(14, paddingCrc, true); lfhView.setUint32(18, P, true); lfhView.setUint32(22, P, true); lfhView.setUint16(26, 11, true); lfhView.setUint16(28, 0, true); lfh.set(new TextEncoder().encode("padding.txt"), 30); // Construct CDFH of padding.txt var cdfh = new Uint8Array(57); var cdfhView = new DataView(cdfh.buffer); cdfh.set([80, 75, 1, 2], 0); cdfhView.setUint16(4, 20, true); cdfhView.setUint16(6, 10, true); cdfhView.setUint16(8, 0, true); cdfhView.setUint16(10, 0, true); cdfhView.setUint16(12, 0, true); cdfhView.setUint16(14, 0, true); cdfhView.setUint32(16, paddingCrc, true); cdfhView.setUint32(20, P, true); cdfhView.setUint32(24, P, true); cdfhView.setUint16(28, 11, true); cdfhView.setUint16(30, 0, true); cdfhView.setUint16(32, 0, true); cdfhView.setUint16(34, 0, true); cdfhView.setUint16(36, 0, true); cdfhView.setUint32(38, 0, true); cdfhView.setUint32(42, 0, true); cdfh.set(new TextEncoder().encode("padding.txt"), 46); // Copy and shift CDFHs var origCd = new Uint8Array(data.subarray(cdStartOffset, cdStartOffset + cdSize)); var shift = 41 + P; var cdView = new DataView(origCd.buffer, origCd.byteOffset, origCd.byteLength); var offset = 0; while (offset < origCd.length - 4) { if (origCd[offset] === 0x50 && origCd[offset+1] === 0x4B && origCd[offset+2] === 0x01 && origCd[offset+3] === 0x02) { var oldOff = cdView.getUint32(offset + 42, true); cdView.setUint32(offset + 42, oldOff + shift, true); var fnLen = cdView.getUint16(offset + 28, true); var extraLen = cdView.getUint16(offset + 30, true); var commentLen = cdView.getUint16(offset + 32, true); offset += 46 + fnLen + extraLen + commentLen; } else { offset++; } } // Copy and modify EOCD var origEocd = new Uint8Array(data.subarray(eocdPos, eocdPos + 22)); var eocdView = new DataView(origEocd.buffer, origEocd.byteOffset, origEocd.byteLength); var oldRecords = eocdView.getUint16(8, true); eocdView.setUint16(8, oldRecords + 1, true); eocdView.setUint16(10, oldRecords + 1, true); var oldCdSize = eocdView.getUint32(12, true); eocdView.setUint32(12, oldCdSize + 57, true); eocdView.setUint32(16, 41 + P + cdStartOffset, true); return [lfh].concat(paddingParts).concat([data.subarray(0, cdStartOffset), cdfh, origCd, origEocd]); } // --- Dynamic tar.gz generation --- function makeTarHeader(filename, fileSize) { var header = new Uint8Array(512); var encoder = new TextEncoder(); header.set(encoder.encode(filename).subarray(0, 100), 0); header.set(encoder.encode("0000644"), 100); header.set(encoder.encode("0000000"), 108); header.set(encoder.encode("0000000"), 116); var sizeStr = fileSize.toString(8).padStart(11, "0") + ""; header.set(encoder.encode(sizeStr), 124); header.set(encoder.encode("00000000000"), 136); header[156] = 48; // '0' (normal file) header.set(encoder.encode("ustar"), 257); header.set(encoder.encode("00"), 263); for (var i = 0; i < 8; i++) { header[148 + i] = 32; } var sum = 0; for (var i = 0; i < 512; i++) { sum += header[i]; } var chkStr = sum.toString(8).padStart(6, "0") + " "; header.set(encoder.encode(chkStr), 148); return header; } function gzipCompressStored(parts, rawSize, crcVal) { var gzipParts = []; var header = new Uint8Array([0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03]); gzipParts.push(header); var blockBuf = new Uint8Array(65535); var blockLen = 0; function pushBlock(isFinal) { var blockHeader = new Uint8Array(5); blockHeader[0] = isFinal ? 1 : 0; var len = blockLen; blockHeader[1] = len & 0xFF; blockHeader[2] = (len >>> 8) & 0xFF; var nlen = ~len; blockHeader[3] = nlen & 0xFF; blockHeader[4] = (nlen >>> 8) & 0xFF; gzipParts.push(blockHeader); gzipParts.push(blockBuf.slice(0, len)); blockLen = 0; } for (var p = 0; p < parts.length; p++) { var part = parts[p]; var offset = 0; while (offset < part.length) { var copyLen = Math.min(part.length - offset, 65535 - blockLen); blockBuf.set(part.subarray(offset, offset + copyLen), blockLen); blockLen += copyLen; offset += copyLen; if (blockLen === 65535) { pushBlock(false); } } } pushBlock(true); // final block var footer = new Uint8Array(8); var fView = new DataView(footer.buffer); fView.setUint32(0, crcVal, true); fView.setUint32(4, rawSize, true); gzipParts.push(footer); return gzipParts; } function generateTarGz(targetSize, spaceChunk) { var S = targetSize - 18; while (18 + 5 * Math.ceil(S / 65535) + S > targetSize) { S--; } var fileSize = S - 1536; var header = makeTarHeader("dummy_test_data.txt", fileSize); var trailer = new Uint8Array(1024); // zeros var crcHeader = crc32(header); var crcSpaces = crcOfSpaces(fileSize); var crcCombined = crc32_combine(crcHeader, crcSpaces, fileSize); var crcFinal = crc32_combine(crcCombined, 0xefb5af2e, 1024); var paddingParts = []; var remaining = fileSize; while (remaining > 0) { var sliceSize = Math.min(remaining, spaceChunk.length); if (sliceSize === spaceChunk.length) { paddingParts.push(spaceChunk); } else { paddingParts.push(spaceChunk.slice(0, sliceSize)); } remaining -= sliceSize; } var rawParts = [header].concat(paddingParts).concat([trailer]); return gzipCompressStored(rawParts, S, crcFinal); } // ===== Main message handler ===== self.onmessage = function(e) { var id = e.data.id; var targetSizeInBytes = e.data.sizeInBytes; var ext = e.data.ext; if (ext === "tar.gz" && targetSizeInBytes >= 1564) { var spaceChunk = new Uint8Array(1024 * 1024); spaceChunk.fill(32); var gzipParts = generateTarGz(targetSizeInBytes, spaceChunk); self.postMessage({ type: "done", id: id, blob: new Blob(gzipParts, { type: "application/octet-stream" }) }); return; } var MAX_UNIQUE = 5 * 1024 * 1024; var sizeInBytes = Math.min(targetSizeInBytes, MAX_UNIQUE); var data; if (ext === "pdf") { data = generateValidPDF(sizeInBytes); } else if (ext === "zip") { data = generateValidZip(sizeInBytes); } else if (ext === "docx") { data = new Uint8Array(minDocx); } else if (ext === "xlsx") { data = new Uint8Array(minXlsx); } else if (ext === "pptx") { data = new Uint8Array(minPptx); } else if (ext === "tar.gz") { data = new Uint8Array(minTarGz); } else if (ext === "rar") { data = new Uint8Array(minRar); } else if (ext === "7z") { data = new Uint8Array(min7z); } else if (ext === "gif") { data = new Uint8Array(minGif); } else if (ext === "webp") { data = new Uint8Array(minWebp); } else if (ext === "png") { data = new Uint8Array(minPng); } else if (ext === "jpg" || ext === "jpeg") { data = new Uint8Array(minJpg); } else if (ext === "mp3") { data = new Uint8Array(minMp3); } else if (ext === "mp4") { data = new Uint8Array(minMp4); } else if (ext === "mkv") { data = new Uint8Array(minMkv); } else if (ext === "avi") { data = new Uint8Array(minAvi); } else if (ext === "mov") { data = new Uint8Array(minMov); } else if (ext === "wav") { data = generateValidWav(sizeInBytes); } else if (ext === "svg") { data = generateSVG(sizeInBytes); } else if (ext === "json") { data = generateJSON(sizeInBytes); } else if (ext === "csv") { data = generateCSV(sizeInBytes); } else if (ext === "xml") { data = generateXML(sizeInBytes); } else if (ext === "html") { data = generateHTML(sizeInBytes); } else if (ext === "sql") { data = generateSQL(sizeInBytes); } else if (ext === "yaml") { data = generateYAML(sizeInBytes); } else if (ext === "css") { data = generateCSS(sizeInBytes); } else if (ext === "js") { data = generateJS(sizeInBytes); } else if (ext === "py") { data = generatePython(sizeInBytes); } else if (ext === "java") { data = generateJava(sizeInBytes); } else if (ext === "go") { data = generateGo(sizeInBytes); } else if (ext === "cpp") { data = generateCpp(sizeInBytes); } else if (ext === "php") { data = generatePHP(sizeInBytes); } else if (ext === "log") { data = generateLog(sizeInBytes); } else if (ext === "md") { data = generateMarkdown(sizeInBytes); } else if (ext === "txt" || ext === "dat") { data = generateTXT(sizeInBytes); } else if (ext === "rtf" || ext === "odt") { data = generateRTF(sizeInBytes); } else if (ext === "sh" || ext === "bat") { data = generateShell(sizeInBytes, ext); } else if (["ini","cfg","conf","properties"].indexOf(ext) >= 0) { data = generateINI(sizeInBytes); } else { data = new Uint8Array(sizeInBytes); } var blobParts = []; var diff = targetSizeInBytes - data.length; if (diff > 0) { var zipExts = ["zip","docx","xlsx","pptx"]; var isZip = (zipExts.indexOf(ext) >= 0); var padSize = isZip ? (targetSizeInBytes - data.length - 98) : diff; if (padSize > 0) { var spaceChunk = new Uint8Array(1024 * 1024); if (ext === "mp3") { var offset = 0; while (offset < spaceChunk.length) { var copySize = Math.min(minMp3.length, spaceChunk.length - offset); spaceChunk.set(minMp3.subarray(0, copySize), offset); offset += copySize; } } else { spaceChunk.fill(32); } var paddingParts = []; var remaining = padSize; while (remaining > 0) { var sliceSize = Math.min(remaining, spaceChunk.length); if (sliceSize === spaceChunk.length) { paddingParts.push(spaceChunk); } else { paddingParts.push(spaceChunk.slice(0, sliceSize)); } remaining -= sliceSize; } if (isZip) { blobParts = padZipInternal(data, targetSizeInBytes, paddingParts); } else { blobParts = [data].concat(paddingParts); } } else { blobParts = [data]; } } else { blobParts = [data]; } self.postMessage({ type: "done", id: id, blob: new Blob(blobParts, { type: "application/octet-stream" }) }); };
Home Generators Any Files Generator

Any Files Generator

Generate large dummy binary or text files for load testing file uploads and evaluating server storage capacities.

File Generator Parameters
.bin (Binary Data File)
Generation Status
Configure parameters and click "Generate & Download" to create mock files.
Done!

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