What Is an EDL (Edit Decision List)? The Complete Guide

An EDL, or Edit Decision List, is a plain-text file that records every cut in a sequence as a pair of timecodes: where each shot starts and ends in the source footage, and where it lands on the finished timeline. No video, no audio, no thumbnails. Just numbers, in a format simple enough to read in a bare text editor and old enough that the machine it was built for has been in a museum for decades.

That combination, dumb and universal, is why it never fully died. When two systems that agree on nothing else need to hand off a cut, an EDL is usually the one file format both of them can open. It has outlasted the hardware that created it, the company that built that hardware, and several generations of software that replaced both. The full definition lives at Wikipedia's entry on the edit decision list, but the short version is: it is a list of where to find something, never what that something looks like.

Origin Story

A joint venture between CBS, Memorex, and a machine called RAVE

The format traces back to 1971 and a company called CMX Systems, a joint venture between CBS and Memorex, hence the name: CBS plus Memorex plus eXperimental. The CMX 600 ran on a DEC PDP-11 minicomputer wired to modified Memorex disk packs standing in for videotape, and CMX marketed it as a RAVE, a Random Access Video Editor. It was built for offline editing: cut a rough version fast on disk, then hand the tape department a list of exactly which frames to conform for air. That list was the first EDL, and it existed for a mundane reason: disk storage in 1971 was small and expensive, so the finished program still had to be assembled from the original videotape rather than played straight off the editing machine.

The 600 was paired with an auto-assembly unit called the CMX-200, and together they set the pattern every later tape-era edit controller followed: cut on one machine, conform on another, and let a list of timecodes be the bridge between them. CMX's later edit controllers became the dominant systems of the linear-tape era, and the list format they wrote became the de facto standard so completely that editors still call any EDL a "CMX3600" regardless of what software actually generated it. A file format born to talk to a room full of 1970s tape machines is still the thing your NLE offers as a default export option in 2026.

Reading the Format

What an event line actually says, left to right

An EDL is an ordered list of events, one line per cut, and each line reads like a short recipe. A typical CMX3600 event looks like this:

014 A004C012 V C 09:12:04:11 09:12:09:21 01:00:22:14 01:00:27:24

Event 14, source reel A004C012, video track, a straight cut, pulled from 09:12:04:11 to 09:12:09:21 in the source, and placed at 01:00:22:14 to 01:00:27:24 on the master timeline. That is five seconds and ten frames of one clip, told entirely through numbers. A dissolve gets written as two linked events sharing a matching cut point instead of one plain cut; a wipe adds a SMPTE-defined effect number for the transition style; a speed change gets its own event flagged with a motion marker. Nothing about the shot itself, color, framing, performance, is in the file. An EDL describes where to find something, never what it looks like, which is exactly why it stays so small.

Stack a handful of these lines and you have described a real cut without moving a single frame of picture. Three events in a row might read as: open on reel A002C004 for four seconds, cut to A004C012 for five and a half, dissolve over half a second into A006C001 to close. Every system that reads CMX3600 turns that same three-line stack into an identical sequence of cuts, because the format leaves no room for interpretation. That predictability, more than anything else, is why it survived four decades of hardware and software turnover that broke almost everything else from the tape era.

Known Limits

Where the format runs out of room, and why that's not a bug

The limits below trace straight back to 1970s hardware constraints, carried forward unchanged, and they still bite people who don't check for them before an export.

• 999 events, hard stop. Event numbers run 001 to 999. A long-form cut with more edits than that has to be split across multiple EDLs, one per reel or one per act.
• Eight-character reel names, seven if there's a dissolve. Long camera-card or clip names get truncated to fit, and truncation is exactly how two different clips end up sharing a name and colliding on conform.
• Four audio channels, at most. A standard CMX3600 EDL cannot describe a modern multitrack audio mix. Treat it as a picture-cut list and hand audio off some other way.
• Drop-frame versus non-drop-frame. The header's FCM flag has to match your actual timecode standard, a distinction we cover in more depth in our guide to timecode. Get it wrong at 29.97fps and every record timecode after the mismatch quietly drifts, frame by frame, until the conform is unusable.
• One or two video tracks, cuts and basic transitions only. Stack more layers than that, or lean on effects, speed ramps, or titles, and none of it survives the export. It gets flattened or dropped, silently.

Color Workflow

How a colorist still opens one today

The place EDLs are least optional is the color suite, in a workflow colorists call pre-conforming. The editor exports a single reference movie of the locked cut plus an EDL. The colorist drops the reference file into DaVinci Resolve, imports the EDL, and Resolve reads the timecode pairs and slices the reference into individual clips on a fresh timeline, each one now addressable and gradeable on its own, without the colorist ever touching the original camera files. The site Mixing Light, which trains colorists on exactly this handoff, walks through moving a timeline into Resolve using an EDL plus reference movie as a standard pre-conform technique.

Nikolai Waldman, a colorist and workflow trainer, put it plainly on his own site: "If you are working in video you will at some point find yourself using an EDL." He also notes a hard ceiling worth remembering: "The maximum amount of audio channels in a standard CMX3600 EDL is 4." The workflow he and other working colorists describe solves a real, unglamorous problem: a colorist grading a project remotely, with no practical way to receive the original camera files, can still conform an accurate cut from nothing but a reference movie and a small text file. That's the entire value proposition of an EDL in one sentence: structure, without the weight of media.

Here is that same pre-conform workflow demonstrated end to end, from an EDL file to a conformed timeline in DaVinci Resolve:

Beyond the Grade

Where else an EDL still turns up

Color grading is the most visible use today, but it isn't the only one. Broadcast and cable networks have long used EDL-style logs to mark exact commercial-break boundaries for ad-insertion and skip-detection systems, because a timecoded list of in and out points is precisely what those systems need and nothing more. Archivists and rights teams use them the same way: a short text file that proves which frames of a master were used where, without shipping the master itself back and forth. A handful of open-source media players, including MPlayer and mpv, also read a simplified EDL dialect of their own to mark sections of a file to skip or mute, a small but telling sign of how far the "timecoded cut list" idea traveled beyond broadcast. None of these uses need a single frame of video attached. They just need the numbers to be right, which is the one thing this format has rarely gotten wrong in fifty-some years.

Format Comparison

EDL, XML, and AAF side by side

Three interchange formats show up in almost every cross-platform handoff, and despite the overlap in what they get used for, they aren't interchangeable with each other.

Format	Carries	Best for	Weak point
EDL (CMX3600)	Cuts, basic dissolves/wipes, source and record timecode, reel names	Widest possible compatibility, color conform	No effects, 1-2 video tracks, 999-event cap, 8-character reel names
XML (FCP XML and its dialects)	Multiple tracks, effects, titles, markers, structure, rich metadata	Editorial handoff between modern NLEs	Dialects vary by app and version, so not every field survives every import, a quirk we go into further in our breakdown of FCPXML
AAF	Timeline structure plus the option to embed or reference actual media and audio	Avid workflows, audio round-trips into Pro Tools	Heavier files, less universal outside Avid-centric pipelines, covered in full in our guide to the AAF file

Reach for an EDL when the receiving system is unknown or ancient and only the cuts matter. Reach for XML or AAF when the edit's detail, effects, layers, or audio has to survive the trip intact. The Advanced Media Workflow Association, which maintains the AAF specification, still positions it as a format built to carry both metadata and media together, which is exactly what an EDL was never designed to do.

The Handoff

Where ScriptCut fits, honestly

ScriptCut is not an NLE and doesn't pretend to be one. It lives at the stage before the timeline, where an editor turns a transcript into a paper edit: read the words, highlight the lines worth keeping, drop the fillers, arrange the order, and get a client's sign-off before anyone opens a cutting tool. If you've never worked inside a transcript-based editor before, that's the shift: you're editing the words on the page, and the cut follows.

Because every selected line in ScriptCut carries a word-level timecode, the export at the end of that process isn't a pile of loose clips, it's an already-ordered sequence. Send it as XML and it opens as a real, already-conformed timeline in DaVinci Resolve, Premiere Pro, Final Cut Pro, or Avid Media Composer, each one reading the same file through its own importer rather than through a shared tape-era list. ScriptCut can also hand off subtitles, a plain transcript, and the audio itself alongside that timeline. The XML export keeps each sound channel of a recording as its own track too, so you're not limited to the handful of channels an older cut-list format could hold. ScriptCut's job ends where the NLE's job begins: it decides the story and the order, then hands off a format the next tool can actually read, the same problem CMX solved with a room of disk packs in 1971, just without the disk packs.

Common Mistakes

Where EDL handoffs actually go wrong

Most EDL problems are predictable once you know the format's ceilings. Reel names get silently truncated and two clips collide under one name on conform. A project shot at 23.976fps gets exported with the wrong FCM flag and every timecode after the first mismatch drifts by a frame, then by several. An editor assumes audio will travel with the EDL and discovers, after the colorist calls, that only four channels made it across. And effects, titles, and speed ramps that looked fine in the NLE vanish entirely in the exported file, because an EDL was never built to describe them in the first place. None of this is a reason to avoid EDLs. It's a reason to know, before you export, exactly what an EDL can and can't carry, and to reach for XML or AAF the moment the cut needs more than straight timecode pairs.

Takeaway

Old format, still the safest bet when you don't know what's on the other end

An EDL survives because it asks for almost nothing: a text file, a shared sense of timecode, and a reel name under nine characters. That minimalism is a limitation everywhere except the one place that matters most: when you genuinely don't know what system is going to open your cut next. Use XML or AAF when detail has to survive the handoff. Use an EDL when only the cuts do. And do the actual storytelling earlier than either, on the transcript, where changing your mind still only costs a few dragged lines instead of a rebuilt timeline. If you want to see what that discipline looks like end to end, paper cut vs paper edit is the next place to look, and exporting a paper edit to Final Cut Pro and Avid shows the handoff in practice. Start that process on your next project at ScriptCut.

Sources

• Edit decision list (Wikipedia)
• CMX 600 (Wikipedia)
• CMX Systems (Wikipedia)
• Nikolai Waldman, How to Read an EDL
• Mixing Light, moving timelines into DaVinci Resolve using EDLs