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Invert PDF Colors (Dark Mode PDF Converter)

Flip page colors (white to black, black to white) to create eye-friendly dark-mode PDFs or fix inverted slide decks.

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or drag and drop your file here

✅ Task Complete!

Continue Your Workflow (Next Recommended Steps):

Next: Compress PDF → Next: PDF Presentation Mode Prep →

How to Use Invert PDF Colors 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 Invert PDF Colors Now to download your output immediately, or continue to related tools like PDF to Grayscale, Annotate PDF, Highlight PDF.

Technical Specifications & Privacy Guarantee

Tool NameInvert PDF Colors (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 Invert PDF Colors

Is the SYCAGO Invert PDF Colors tool completely free?

Yes. Invert PDF Colors 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 Invert PDF Colors?

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

PDF to Grayscale

Transform color graphics and text into balanced luminance grayscale for economical black-and-white printing.

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Annotate PDF

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

100% Browser-Based Use Tool →

Highlight PDF

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

100% Browser-Based Use Tool →

PDF Presentation Mode Prep

Embed `/PageMode /FullScreen` and `/ViewerPreferences` flags so your PDF slide deck launches like a keynote presentation.

100% Browser-Based Use Tool →

Compress PDF

Shrink oversized PDFs by stripping redundant metadata, compressing object streams, and downsampling heavy page bitmaps.

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' + 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; } }); });