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Annotate PDF with Callouts, Stamps & Markup

Apply visual review banners, bordered callout boxes, and status stamps directly onto selected PDF pages.

📄

or drag and drop your file here

✅ Task Complete!

Continue Your Workflow (Next Recommended Steps):

Next: Flatten PDF → Next: Compress PDF →

How to Use Annotate PDF Online

  1. Upload Your Document: Click the Select File button above or drag and drop your .pdf file into the dashed box.
  2. Configure Your Settings: Review the tool options and preview thumbnails. Because SYCAGO processes files directly inside your browser, your sensitive data stays private on your device.
  3. Download or Chain to Next Tool: Click Process Annotate PDF Now to download your output immediately, or continue to related tools like Highlight PDF, Add Comments to PDF, Add Text to PDF.

Technical Specifications & Privacy Guarantee

Tool NameAnnotate PDF (SYCAGO PDF Suite)
Accepted Input Formats.pdf (Single file)
Processing Architecture100% Browser-Based (Client-Side HTML5 / WebAssembly)
Data PrivacyFiles are processed locally in your browser memory and are never stored on third-party servers.

Frequently Asked Questions About Annotate PDF

Is the SYCAGO Annotate PDF tool completely free?

Yes. Annotate PDF runs 100% free in your browser with no watermarks, no daily registration walls, and no hidden fees.

Are my PDF files uploaded to a remote server?

No. This tool uses 100% Browser-Based technology (powered by WebAssembly and HTML5 Canvas), meaning your PDF files are parsed and generated directly inside your own web browser for complete confidentiality.

What should I do after using Annotate PDF?

Once your file is processed, you can download it immediately or click any of the recommended next-step buttons in the completion panel to jump straight to companion tools in our PDF Tools Hub.

Related PDF Tools

Highlight PDF

Place translucent neon highlight bars over key clauses or paragraphs on any PDF page.

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Add Comments to PDF

Stamp a formatted reviewer note card (with Reviewer Name, Date, and Comment text) onto the margin of any PDF page.

100% Browser-Based Use Tool →

Add Text to PDF

Type text directly onto any PDF page with customizable position, font size, and color.

100% Browser-Based Use Tool →

Sign PDF

Draw your signature on an interactive pad, include an optional date stamp, and apply it to the first, last, or all pages.

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Flatten PDF

Convert interactive form inputs and floating stamps into permanent, non-editable page content.

100% Browser-Based Use Tool →
' + htmlBody.join('') + ''; offerDownload(new Blob([docHtml], {type:'application/msword'}), baseName + '.doc', 'Extracted ' + pdfDoc.numPages + ' page(s) into an editable Word document.'); } else if(engine === 'pdf-to-excel' && window.XLSX){ var aoa = csvRows.map(function(r){ return r.split(',').map(function(c){return c.replace(/^"|"$/g,'');}); }); var wb = XLSX.utils.book_new(); var ws = XLSX.utils.aoa_to_sheet(aoa); XLSX.utils.book_append_sheet(wb, ws, 'Extracted_PDF'); var wbout = XLSX.write(wb, {bookType:'xlsx', type:'array'}); offerDownload(new Blob([wbout], {type:'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet'}), baseName + '.xlsx', 'Exported tabular data across ' + pdfDoc.numPages + ' pages to Excel (.xlsx).'); } else if(format === 'csv' || engine === 'extract-tables'){ offerDownload(new Blob([csvRows.join('\n')], {type:'text/csv;charset=utf-8'}), baseName + '.csv', 'Extracted ' + csvRows.length + ' rows to CSV.'); } else if(format === 'html' || engine === 'pdf-to-ppt'){ var fullHtml = '' + baseName + ' ' + htmlBody.join('') + ''; offerDownload(new Blob([fullHtml], {type:'text/html;charset=utf-8'}), baseName + (engine==='pdf-to-ppt'?'-slides.html':'.html'), 'Converted ' + pdfDoc.numPages + ' pages.'); } else if(format === 'rtf'){ var rtf = '{\\rtf1\\ansi\\deff0 {' + joinedTxt.replace(/\n/g, '\\par\n') + '}}'; offerDownload(new Blob([rtf], {type:'application/rtf'}), baseName + '.rtf', 'Exported Rich Text Format (.rtf) document.'); } else { offerDownload(new Blob([joinedTxt], {type:'text/plain;charset=utf-8'}), baseName + '.txt', 'Extracted ' + joinedTxt.split(/\s+/).length + ' words across ' + pdfDoc.numPages + ' page(s).
'); } } // 9. WORD / EXCEL / TXT / MARKDOWN / HTML TO PDF else if(['word-to-pdf','excel-to-pdf','text-to-pdf'].indexOf(engine) !== -1){ var textContent = (rawTextEl && rawTextEl.value.trim()) ? rawTextEl.value.trim() : ''; if(!textContent && selectedFiles.length){ var f = selectedFiles[0]; if(engine === 'word-to-pdf' && window.mammoth && f.name.toLowerCase().endsWith('.docx')){ var res = await mammoth.extractRawText({arrayBuffer: await f.arrayBuffer()}); textContent = res.value; } else if(engine === 'excel-to-pdf' && window.XLSX){ var wb = XLSX.read(await f.arrayBuffer(), {type:'array'}); textContent = XLSX.utils.sheet_to_csv(wb.Sheets[wb.SheetNames[0]]); } else { textContent = await f.text(); } } var outPdf = await PDFLib.PDFDocument.create(); var font = await outPdf.embedFont(PDFLib.StandardFonts.Helvetica); var rawLines = textContent.replace(/\r/g,'').split('\n'); var wrapped = []; rawLines.forEach(function(l){ while(l.length > 85){ wrapped.push(l.slice(0,85)); l = l.slice(85); } wrapped.push(l); }); var pg = outPdf.addPage([595.28, 841.89]); var y = 790; wrapped.forEach(function(line){ if(y < 50){ pg = outPdf.addPage([595.28, 841.89]); y = 790; } var clean = line.replace(/[^\x20-\x7E]/g, ' '); pg.drawText(clean, {x: 45, y: y, size: 10.5, font: font}); y -= 15; }); var b = await outPdf.save(); offerDownload(new Blob([b], {type:'application/pdf'}), baseName + '.pdf', 'Generated ' + outPdf.getPageCount() + '-page PDF document.'); } // 10. OCR PDF & OCR IMAGE (Tesseract.js WASM) else if(engine === 'ocr-pdf' || engine === 'ocr-image'){ if(!window.Tesseract) throw new Error('OCR engine is still loading, please try again in a moment.'); var ocrResultText = []; if(engine === 'ocr-image'){ statusEl.textContent = '🔍 Running Optical Character Recognition on image...'; var r = await Tesseract.recognize(selectedFiles[0], 'eng'); ocrResultText.push(r.data.text); } else { var pdfDoc = await pdfjsLib.getDocument({data: await selectedFiles[0].arrayBuffer()}).promise; var maxOcrPages = Math.min(pdfDoc.numPages, 10); for(var p=1; p<=maxOcrPages; p++){ statusEl.textContent = '🔍 Running OCR on page ' + p + ' of ' + maxOcrPages + '...'; var page = await pdfDoc.getPage(p); var vp = page.getViewport({scale: 1.8}); var cnv = document.createElement('canvas'); cnv.width = vp.width; cnv.height = vp.height; await page.render({canvasContext: cnv.getContext('2d'), viewport: vp}).promise; var r = await Tesseract.recognize(cnv, 'eng'); ocrResultText.push('--- Page ' + p + ' ---\n' + r.data.text); } } var finalOcr = ocrResultText.join('\n\n'); offerDownload(new Blob([finalOcr], {type:'text/plain;charset=utf-8'}), baseName + '-ocr-text.txt', 'OCR complete! Extracted ' + finalOcr.split(/\s+/).length + ' words.
'); } // 11. DIAGNOSTIC INSPECTORS / PAGE COUNTER / FORM FILLER / COMPARE / BATCH RENAME else if(['inspector','page-counter','form-filler','compare-visual','compare-text','batch-rename'].indexOf(engine) !== -1){ if(engine === 'page-counter'){ var rows = ['Filename,Pages,Size_KB'], totalP = 0, htmlRows = ''; for(var i=0;i' + c + '' + (selectedFiles[i].size/1024).toFixed(1) + ' KB'; } offerDownload(new Blob([rows.join('\n')], {type:'text/csv'}), 'pdf-page-count-report.csv', 'Total Pages Across ' + selectedFiles.length + ' Files: ' + totalP + '' + htmlRows + '
FilePagesSize
'); } else if(engine === 'batch-rename' && window.fflate){ var pat = ((document.getElementById('syc-opt-pattern') || {}).value || 'SYCAGO_{seq}_{name}'); var zipR = {}; for(var i=0;i' + report + ''); } else if(engine === 'form-filler'){ var src = await PDFLib.PDFDocument.load(await selectedFiles[0].arrayBuffer(), {ignoreEncryption:true}); var form = src.getForm(); var fields = form.getFields(); fields.forEach(function(f){ try { if(f.setText) f.setText(f.getName() + ' [Filled]'); } catch(e){} }); var b = await src.save(); offerDownload(new Blob([b], {type:'application/pdf'}), baseName + '-filled.pdf', 'Detected and processed ' + fields.length + ' interactive AcroForm field(s).'); } else { var ab = await selectedFiles[0].arrayBuffer(); var headerStr = new TextDecoder().decode(ab.slice(0, 1024)); var verMatch = headerStr.match(/%PDF-(\d\.\d)/); var pdfVer = verMatch ? verMatch[1] : '1.7'; var d = await PDFLib.PDFDocument.load(ab, {ignoreEncryption:true}); var pDoc = await pdfjsLib.getDocument({data: ab}).promise; var infoRows = [ ['File Name', selectedFiles[0].name], ['File Size', (selectedFiles[0].size/1024).toFixed(2) + ' KB'], ['PDF Spec Version', 'PDF ' + pdfVer], ['Page Count', d.getPageCount()], ['Title', d.getTitle() || '(None)'], ['Author', d.getAuthor() || '(None)'], ['Creator / Producer', (d.getCreator() || '-') + ' / ' + (d.getProducer() || '-')], ['AcroForm Fields Count', d.getForm().getFields().length], ]; if(mode === 'page-sizes'){ d.getPages().slice(0, 20).forEach(function(pg, idx){ var s = pg.getSize(); infoRows.push(['Page ' + (idx+1) + ' Dimensions', (s.width*0.3527).toFixed(1) + ' × ' + (s.height*0.3527).toFixed(1) + ' mm (' + Math.round(s.width) + ' × ' + Math.round(s.height) + ' pt)']); }); } var tbl = '' + infoRows.map(function(r){ return ''; }).join('') + '
' + r[0] + '' + r[1] + '
'; var jsonBlob = new Blob([JSON.stringify(Object.fromEntries(infoRows), null, 2)], {type:'application/json'}); offerDownload(jsonBlob, baseName + '-' + mode + '-report.json', tbl); } } } catch(err){ statusEl.textContent = '⚠️ Error: ' + (err.message || 'Unable to process file. Please verify the file is a valid PDF.'); } finally { runBtn.disabled = false; } }); });