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How to edit PDF in a browser and add text, signatures, and images

DevelopTools can place new text, images, and drawings over an existing page. It cannot rewrite existing paragraphs within a PDF itself.

Flow for adding text and a handwritten signature to a dummy PDF
Flow for adding text and a handwritten signature to a dummy PDF

Edit PDF in browser

You can load a PDF, perform the necessary operations while checking Thumbnail and Preview, and save it as a separate PDF from the original file.

Open PDF editing tool

Conclusion: Choose elements to add, place them on the page, and inspect the saved PDF

You can add text, highlights, rectangles, circles, lines, handwriting, images, and signatures. For the selected element, you can adjust position, size, color, transparency, and text decoration.

This is not editing existing text, OCR, true redaction, or electronic certificate signing. Even if the appearance is similar, the security implications differ.

Load PDF and check target page

Check the target page, appended content, font in use, and image format.

Account to checkOperation/displayjudgment
TextText tool and font settingsConsider loading Japanese font files.
ImagePNG/JPEG/WebPTransparency and aspect ratio
signatureHandwriting dialogVisual signature
ShapesFluorescent, square, circle, and lineOriginal content remains

Perform editing operations

Select a type from the Toolbar and place it on the Page.

  1. Open the PDF.
  2. Select text, images, signatures, and more.
  3. Add it to the Page and adjust its position and Size.
  4. Set color, font, and opacity.
  5. Save after checking the Preview.

Check with Preview and save as a new PDF

Check the page number, order, orientation, and position of additional elements in Preview. Reopen the saved PDF and check that nothing other than the target page has changed.

confirmationplaces to seePoints to prevent failure
PageThumbnail / Page numberCheck for missing/duplicated/sequence
DisplayCenter preview and zoomCheck direction, position, and cut
outputPDF after savingCheck the number of pages, filename, and file size.

Distinguish between easily confused functions in PDF editing

ActionsWhat this tool meansnot respond
Add charactersDraw a new text element onto the PageEdit existing Paragraph directly
handwritten signatureAdd drawn appearance to PDFDigital Signature with electronic certificate
squareAdd shapes to the pageRedaction to remove the original Text
Page displayPreview Page with PDF.jsImage PDF OCR
Save current pageOutput the currently displayed page to another PDFSpecify Range/Batch Extract Multiple Pages

Even if you cover the text with a black rectangle, the original Text Object may remain. For redacting personal and sensitive information, use a product that has true Redaction capabilities and can verify original data removal.

Notes on in-browser processing and confidential PDFs

DevelopTools PDF editing processes the selected PDF Binary, Filename, signature, and Form input on Browser Memory without sending them to the Application Server. Content Security Policy also prohibits external connections.

However, we do not guarantee the safety of devices, browsers, extensions, screen sharing, or download destinations. For confidential documents, it is also necessary to check the regulations of the user organization, device management, storage location, and edited file.

The original PDF will not be directly overwritten. Save the edited PDF under a different name and check the content, page order, orientation, searchable text, metadata, etc. according to your needs.

Compatible range of PDF editing tools

CategoryActionsSupported
loadingPDF selection/Drag & Drop/Add multiple PDFsSupported
Page operationsMove forward/backward/duplicate/add/delete blank pages/rotate left/right 90 degreesSupported
extractionSave current page as separate PDFOnly 1 page supported
P.S.Text/fluorescence/shapes/lines/handwriting/images/handwritten signaturesSupported
formExisting fillable Form FieldIf the PDF has a field
SaveDownload the entire or current page as a new PDFSupported
UnsupportedDirect rewriting of existing text, OCR, decryption, authentic Redaction, digital certificate signatureNot compatible

Check implementation and official documentation

The structure of PDF differs depending on the creation application, font, encryption, form, annotation, image format, etc. Don't make a judgment based only on the steps in the article, check the compatibility range of the Tool and Library you are using, and the output PDF.

Example: Add a name and handwritten signature to an application form

Add names with the text tool and signatures from the handwritten signature dialog.

After saving, check for mojibake, position, and clipping.

  1. Add a name
  2. Check Japanese fonts
  3. Add signature
  4. Post-save check

When handling real signatures, also check the sharing destination, storage location, and device security.

Frequently asked questions

Can I rewrite existing text in PDF like in Word?
No. Develop Tools adds text and images to existing pages. It cannot re-edit existing paragraphs or replace fonts.
Are PDFs and signatures sent to the server?
Not sent. Load, edit, preview, and output PDFs within the Browser. The user is responsible for confirming the storage location and device management after downloading.
Can I edit password-protected PDFs and scanned PDFs?
Decryption of encrypted PDF and OCR are not supported. If you are unable to read the file, please prepare Copy or an OCR compatible product with the protection removed with proper authority.