Merge videos
Join separately recorded clips or split recordings into one video in the order you choose. Different resolutions and codecs are fine; everything is fitted to the first video.
Settings
How to use
- 1
Add videos
Drop the videos in order. Use the up and down buttons to reorder them.
- 2
Choose format and fit
The resolution follows the first video. Videos of other sizes are fitted inside or cropped to fill.
- 3
Merge and save
Everything is re-encoded, so processing time scales with the total length.
How merging works
Each video is decoded in turn and re-encoded into one file with shifted timestamps, so inputs with different formats and codecs can be joined. The resolution follows the first video; the others are fitted inside (with bars) or cropped to fill.
Audio follows the sample rate of the first video that has sound, and silent stretches are inserted for videos without audio. Because everything is re-encoded, processing time scales with the total length.
Frequently asked questions
How is the order decided?
Videos are listed in the order added. Use the up and down buttons to reorder them.
Can I merge videos of different resolutions?
Yes. They are fitted to the first video’s resolution: “Fit inside” adds bars, “Fill box” crops the overflow.
Is quality lost?
Merging re-encodes everything, so it changes slightly according to the Quality setting. At “High” or above the difference is negligible.
How many videos can I merge?
There is no limit on count, but the output is held in memory before saving, so totals of several gigabytes may fail.
Help us improve the service
If a conversion fails, sending us the circumstances helps us track down the cause. Knowing which devices and formats fail most often, and how long processing takes, lets us revise the supported formats and fix the bugs behind them. If you don't mind, leaving this on is a real help.
What is sent
- The tool you used and the settings you chose (output format, quality, etc.)
- Your device specs (GPU, memory, core count)
- The input format with a rough size
- How many files succeeded or failed and how long it took
- The error type and details when something fails
What is never sent
- The files themselves and file names
- Text, subtitles or prompts you add to a video
- The text to be read aloud, voice descriptions, the pronunciation dictionary and saved voices
- The text in PDFs, the text you rewrote or redacted, passwords, font names and the page ranges you enter
- IP addresses
The data goes only to this site's own server, never to a third-party service.
Details sent by specific tools (counts, times, kinds and yes/no only)
In addition to “What is sent”, text to speech and the PDF tools send the following details.
- Text to speech
- The approximate number of characters and sentences, how many parts the text was generated in, and how long the AI model took to load.
- PDF tools (all)
- The page count range, whether editing is restricted, whether a permissions password was entered, and whether the PDF is signed or encrypted.
- PDF text editing and redaction
- The numbers of rewrites, deletions, white-outs and redactions, the number of rewritten characters by source (original font or fallback font, the latter as a range) and the fallback typeface, the kinds of reasons why lines cannot be edited, and the number of pages turned into images by redaction and the reasons.
- PDF page operations and conversion between images and PDF
- The numbers of inputs and outputs, of pages rotated, deleted, duplicated or moved, of images inserted as they are, converted, in HEIC format or with corrected orientation, and of pages rendered at a lower resolution (all as ranges), whether the original was updated in place or a new document was created, and whether the original protection was reapplied, form fields were written into the page and bookmarks were added back.
- PDF compression
- The numbers of inputs and outputs, of images downsized, not downsized and black-and-white, of downsized images whose transparency was also downsized, that stayed lossless or that were converted from CMYK to RGB, and how many times the file was compressed (all as ranges), the kinds of reasons images were not downsized, whether the target size was met and the kind of reason it was not met, the range of how much smaller the file got, whether the original protection was reapplied, and whether the original PDF was returned unchanged.
- PDF cropping and page numbers
- The numbers of inputs and outputs and of pages cropped, numbered or with their margins reduced (all as ranges), how the margins were set, how the pages to crop or number were chosen, the number format and position, the range of the starting number, that the original was updated in place, and whether the original protection was reapplied.