How to Add or Replace Text in a PDF

Is the text real text, or part of an image?

Before you try to change anything, work out which kind of text you are looking at, because the two behave completely differently. Open the PDF and try to select a word with your cursor. If a text selection highlight appears, the page has a real text layer you can work with. If nothing selects — the whole page acts like a single picture — it is a scanned or exported image, and there is no text to edit until it has been through OCR.

A third case sits in between: text that has been converted to outlines (vector shapes) during export. It looks like text and may even select as a block, but each glyph is a shape, not a character, so it cannot be retyped. In that case you add a new text box over the top rather than editing in place.

When should you add a text box?

Adding a text box is the right move whenever you are placing something that is not already there, or when the underlying text cannot be edited directly. Typical jobs: writing a name or date onto a form, adding a reference number, labelling a diagram, or covering an old value with a filled rectangle and typing the new one on top.

1. 1Open the PDF in the editor and go to the page you need.
2. 2Choose the text tool and click where the text should start.
3. 3Type the content, then set the font, size, and colour to match the surrounding text as closely as you can.
4. 4Drag the box to align it with the existing baseline, and nudge it with the arrow keys for fine positioning.
5. 5If you are replacing a visible value, add a rectangle in the page background colour over the old text first, then put the new text box above it.

Can you change an existing text object instead?

Where the PDF has a live text layer, you can often edit a short run of existing text in place — fix a typo, change a figure, swap a word. This works best on simple, single-column content set in a common font. It is not a substitute for a word processor: the editor does not reflow a paragraph when your edit makes a line longer or shorter, so a change that adds several words can push text past the margin or overlap the next line. For anything longer than a few words, replacing the whole line or block is more reliable than editing within it.

Why does the font look different after editing?

PDFs embed the specific fonts they were built with, and that exact font file may not be available to the editor. When it is not, your new or edited text is rendered in the closest substitute, which can differ in weight, letter spacing, or shape. This is normal and happens in every PDF editor, not just this one. The practical fix is to keep edits short and visually consistent, and to check the result at full zoom before you download.

Does OCR make a scanned PDF editable?

OCR adds a searchable text layer to a scan by reading the page images and transcribing them. That makes the text selectable and searchable, and it lets you place text boxes accurately against what is on the page. It does not turn the scan into a clean, fully reflowable document — the original remains a picture underneath the new text layer. Run the scan through PDF OCR first, then use the editor to add or cover text as needed.

What to check before you download

• ·Read every page at 100% and again at 200% — misaligned baselines and colour mismatches only show up at zoom.
• ·Confirm no added text crosses into a margin or overlaps a line below it.
• ·If you covered old text with a rectangle, check the fill colour matches the page exactly, with no visible seam.
• ·Select your new text to confirm it is real text (useful if the file will be searched later), unless you deliberately flattened it.
• ·Keep the original file. The editor exports a new copy, so your source PDF is untouched and available if an edit needs redoing.

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