Does Interleave PDFs upload my file or text to Tool-You servers?

No. Interleave PDFs runs in this browser tab. Files stay on the device. Limit note: Alternates two PDFs. Choose which file starts.

Should I use Merge PDF instead of Interleave PDFs?

Use Interleave PDFs when you need Alternate pages from two PDFs. Use Merge PDF when you need Combine multiple PDFs into one file, in your chosen order—right in the browser. They share a category (PDF) but not the same job.

Interleave PDFs

Alternate pages from two PDFs.

Takes PDF A then PDF B. Output is A1, B1, A2, B2. Extra pages from the longer file append at the end. Unlike Merge this is not A then all of B. Unlike Overlay pages are not stacked.

What Interleave PDFs does

Takes PDF A then PDF B. Output is A1, B1, A2, B2. Extra pages from the longer file append at the end. Unlike Merge this is not A then all of B. Unlike Overlay pages are not stacked.

Practical limit for Interleave PDFs: Alternates two PDFs. Choose which file starts. That is why output can differ from heavy desktop PDF software. Read the tool-specific note again: Takes PDF A then PDF B. Output is A1, B1, A2, B2. Extra pages from the longer file append at the end. Unlike Merge this is not A then all of B. Unlike Overlay pages are not stacked.

How to use Interleave PDFs

Stay on this Interleave PDFs page (/interleave-pdf). Do not switch to Merge PDF unless you actually want Combine multiple PDFs into one file, in your chosen order—right in the browser..
Add the file type Interleave PDFs accepts. Hint from the path: interleave pdf. Alternate pages from two PDFs.
Set only the options that match Interleave PDFs. Neighbor Overlay PDF does something else (Stamp one PDF onto another.). Tool note: Takes PDF A then PDF B. Output is A1, B1, A2, B2. Extra pages from the longer file append at the end. Unlike Merge this is not A then all of B. Unlike Overlay pages are not stacked.
Run Interleave PDFs in this tab. Browser memory still applies: Alternates two PDFs. Choose which file starts.
Download or copy the result from Interleave PDFs. If it is the wrong job, open Merge PDF instead.

When not to use Interleave PDFs

Skip Interleave PDFs when a neighbor tool matches better — start with Merge PDF or Overlay PDF — or when the description already warns the job will fail. In the tool’s own words: Takes PDF A then PDF B. Output is A1, B1, A2, B2. Extra pages from the longer file append at the end. Unlike Merge this is not A then all of B. Unlike Overlay pages are not stacked.

Questions about Interleave PDFs

What does Interleave PDFs do that other PDF pages on this site do not?: Takes PDF A then PDF B. Output is A1, B1, A2, B2. Extra pages from the longer file append at the end. Unlike Merge this is not A then all of B. Unlike Overlay pages are not stacked. Short version: Alternate pages from two PDFs.
Does Interleave PDFs upload my file or text to Tool-You servers?: No. Interleave PDFs runs in this browser tab. Files stay on the device. Limit note: Alternates two PDFs. Choose which file starts.
Should I use Merge PDF instead of Interleave PDFs?: Use Interleave PDFs when you need Alternate pages from two PDFs. Use Merge PDF when you need Combine multiple PDFs into one file, in your chosen order—right in the browser. They share a category (PDF) but not the same job.
What are the limits of Interleave PDFs?: Alternates two PDFs. Choose which file starts. Also: Takes PDF A then PDF B. Output is A1, B1, A2, B2. Extra pages from the longer file append at the end. Unlike Merge this is not A then all of B. Unlike Overlay pages are not stacked.