How to use 123 PDF Editor PRO

▶ 1. Getting started

Click the toolbar icon to open the editor in a full browser tab. From the welcome screen you can open an existing PDF, create a new one, or merge and split files.

1. Click Choose a PDF (or Open PDF) and pick a file from your computer.
2. Use Create a new PDF to start from a blank page or a template, or Merge/Split PDF to combine several files.
3. Edit using the top toolbar tools; use Undo (↶) and Redo (↷) at any time.
4. Click Save Project to keep your work in the browser, or Projects to reopen a saved one.
5. When finished, click Download PDF to save the edited file to your device.

✍️ 2. Edit text

Change the words that are already in your PDF. The editor reads the original font, size and colour so replacements match the surrounding text.

1. In the top bar choose a selection mode: Word, Text block, or Select image.
2. Click the text you want to change — the side panel shows the detected font, size and colour.
3. Type your new text, then adjust the font (13 available), size, colour and style (bold, italic, underline, strikethrough, alignment).
4. Leave Auto-expand box to fit text on so the box grows with your content.
5. Use Remove selected text to delete a block. Changes apply automatically.

▧ 3. Images

Move, resize, replace or delete any picture in the document — and add new ones from your device.

1. Switch to ▣ Select image mode and click a picture in the PDF.
2. Drag the blue box to move it; use the bottom-right handle to resize (hold Shift for free proportions).
3. Click Replace with local image to swap it, or Remove image to delete it.
4. To add a new picture, use ▧ Add Image from the Insert bar and place it on the page.

＋ 4. Insert elements

The Insert bar adds new content: text boxes, images, tables, signatures and full template pages.

1. Add Text — draw a text box anywhere, then set font, size, colour and background.
2. Add Table — choose rows, columns, header labels and colours, then place and resize it like an image.
3. Add Template Page — insert a ready-made, editable page (invoice, resume, contract and more).
4. Add Signature — drop a stored signature image onto the page.

◩ 5. Headers, watermarks & page numbers

Add repeating elements across the whole document or a page range: page numbers, headers, footers, watermarks, backgrounds, highlights and dates.

1. # Page Numbers — pick a format (1 · Page 1 · Page 1 of 10 · - 1 -), a start number, position and margin.
2. ⇧ Header / ⇩ Footer — add repeating text; use {page} and {pages} placeholders, and an optional separator line.
3. ◩ Watermark — set the text, opacity and rotation, then apply to all or selected pages.
4. ◫ Background — apply a solid colour or a local image behind the page content.
5. ▰ Highlighter and Date — highlight a word or line, or stamp a date onto the page.

✎ 6. Signatures

Two ways to sign: drop a signature image, or apply a cryptographic digital signature from a local certificate.

1. Image signature: open Add Signature, upload a PNG or JPG (transparent PNG works best), select it and click Place selected signature.
2. Digital signature: open Digital Signature, choose a .p12/.pfx certificate and enter its password.
3. Pick a profile (PAdES-B or Adobe PKCS#7), fill in name, reason, location and contact, and optionally place a visible signature.
4. Click Digitally sign and download. The certificate and password stay in memory only.

▤ 7. Fill & create forms

Complete existing interactive forms, or build your own fillable fields that stay interactive in the downloaded PDF.

1. ▤ Fill Form — type directly into the form fields already present in the document.
2. ▥ Create Form — choose a field type: text, multiline, checkbox, radio, dropdown, list box or button.
3. Set the field name, default value, colours, border, and options such as Required or Read only.
4. Drag a rectangle on the page to place the field. Buttons can open links, jump to a page, submit or reset the form.

▦ 8. Page Organizer

Rearrange the document visually: reorder by dragging, rotate, duplicate, crop and resize pages.

1. Open ▦ Page Organizer and drag pages into the order you want.
2. Use Rotate left/right, Duplicate page, Add blank page or Add Template Page.
3. Crop page with millimetre margins, or Resize to A4, Letter, Legal or a custom size.
4. Click Apply page changes to bring the new layout back into the editor.

⧉ 9. Merge & split

Combine several PDFs into one, or extract and split pages into separate files.

1. Merge: in the Page Organizer choose Merge multiple PDFs, add your files, arrange them and click Import.
2. Extract: select the pages you need and click Extract selected pages.
3. Split: set Split every N pages and click Split PDF to produce separate documents.

◎ 10. Local OCR

Recognise text in scanned pages so it becomes selectable and editable — completely offline.

1. When a scanned page is detected, the Scanned pages detected dialog appears (or open ◎ Local OCR manually).
2. Choose the document language, or leave Automatic to load all 10 bundled languages.
3. Click Run local OCR and wait for the progress bar to finish.
4. The recognised text becomes editable, so you can correct or reuse it like any other text.

▧ 11. Annotations & comments

Review documents with notes, highlights and shapes that stay editable in compatible PDF readers.

1. Open ▧ Annotations & Comments and pick a tool: sticky note, comment, rectangle, circle, highlighter, check or uncheck mark.
2. Click or drag on the page to place it, then fill in the author, subject and comment.
3. Set colour and opacity, choose whether it prints, and mark a comment as resolved when handled.

◆ 12. Protection & privacy

Encrypt the document, control what readers may do, and remove hidden data before sharing.

1. Under Password protection, set an open password (and an optional owner password) and choose AES-256 or RC4.
2. Under Allowed actions, tick which operations readers may perform (printing, copying, modifying, annotating and more).
3. Under Privacy cleanup, remove metadata, comments, links, JavaScript, attachments or flatten form fields.
4. Click Protect / sanitize and download.

⇲ 13. Compress

Reduce file size for email or the web without uploading the document.

1. Open ⇲ Compress and choose a profile: Web, Email or Print.
2. Fine-tune resolution (DPI) and image quality, and optionally convert pages to grayscale.
3. Enable Preserve selectable text, links and form fields if you need them to stay interactive.
4. Click Compress and download.

⌕ 14. Search & replace

Find text anywhere in the document and, when you like, replace it in one pass.

1. Use Search in PDF in the Insert bar to jump between matches.
2. Open ⌕ Search & Replace to enter search and replacement text.
3. Toggle Case sensitive or Whole words only, then use Replace next or Replace all.

⚙ 15. Settings

Adjust language, theme and defaults, and check for updates.

1. Set the interface language (English, Italian, Spanish, French, German, Portuguese or automatic).
2. Choose a theme: System, Light, Dark or High contrast.
3. Pick the default text selection mode and manage automatic update checks.

★ 16. Free vs PRO

Every tool works in the free version. PRO removes the limits with a single one-time payment.

• ✓ Free: all tools, 5 PDF downloads and 3 saved projects in total; OCR exports carry a small Free Version banner.
• ✓ PRO ($24 one-time): unlimited downloads and projects, and clean OCR exports.