Trim HEVC

How to Trim an HEVC File Online

1. Upload Your HEVC File: Drag and drop or click "Add Files" to select an HEVC (H.265) file — raw .hevc/.h265 elementary streams from FFmpeg, screen recorders, IP cameras, or .hevc-renamed iPhone captures all work. Batch is supported — drop in multiple HEVC files at once.
2. Set Start Time and Duration: Enter a start time and a duration to keep. Both fields accept seconds (12.5) or HH:MM:SS.sss format (00:01:30.500) for millisecond precision. Add multiple trim segments to extract several clips from one HEVC stream in a single pass.
3. Pick Output Mode (Optional): Default keeps the original H.265 stream for a stream-copy-style result with zero quality loss — the trimmed bytes are bit-identical to that section of the source. Switch to re-encode if you need frame-accurate cuts or a different codec: choose H.264 (universal compatibility), AV1 (~30% smaller than H.265), VP9, MPEG-4, or stick with HEVC at a different bitrate. Pair with a resolution preset (2160p, 1440p, 1080p, 720p, 480p, percentage, or custom width/height) and a quality preset (Highest → Lowest), CRF slider (18 = visually lossless, 23 = default, 28 = smaller), constant bitrate, or target file-size percentage.
4. Trim and Download: Click Trim. Files process in your browser session — download individually or as a ZIP. No sign-up, no watermark, no length cap on the output.

Why Trim HEVC Files?

HEVC (H.265) is the successor to H.264 — it delivers roughly the same visual quality at half the bitrate, which is why Apple made it the default capture codec on iPhone since iOS 11 (2017), why UHD Blu-ray uses it exclusively, and why most 4K security cameras, drones, and action cams record in it. A raw .hevc file is the elementary stream without a container, common in FFmpeg pipelines, IP-camera dumps, and developer workflows. Trimming with stream copy keeps every byte of the original stream intact, which matters because re-encoding HEVC is slow and risks quality loss. Common reasons to trim:

• iPhone HEVC clips for sharing — iPhone 7 onward records H.265 by default (Settings → Camera → Formats → High Efficiency). A 4-minute 4K HEVC capture is ~400 MB; trim to a 30-second highlight before sharing so it slips under Discord 10 MB / WhatsApp 16 MB / Gmail 25 MB caps. For Windows recipients who can't play HEVC without the paid Microsoft codec, follow up with HEVC to MP4 (re-encode to H.264).
• 4K drone and action-cam footage — DJI Mini 4 Pro, Mavic 3, GoPro Hero 12, and Insta360 Ace Pro all record 4K/60 in HEVC. A 10-minute flight is multi-GB; trim to the cinematic 90-second cut before color grading in DaVinci Resolve or pushing to YouTube.
• Security and IP-camera review — Reolink, Hikvision, and Dahua cameras export HEVC clips. Trim the 30-second window where the package was delivered out of an 8-hour recording without re-encoding the whole thing.
• UHD Blu-ray remux extracts — A 2-hour 4K Blu-ray remux is 50-80 GB of HEVC. Stream-copy trim a single fight scene or musical number to ~500 MB while preserving HDR10 / HDR10+ / Dolby Vision metadata exactly.
• FFmpeg pipeline outputs — Developers and broadcast engineers often work with raw .hevc annexb streams. Trim a segment for analysis, regression testing, or hand-off to a downstream tool without remuxing back into MP4/MKV.
• Sharing under email and chat caps — Gmail caps at 25 MB, Outlook at 20 MB, Discord at 10 MB free / 25 MB Nitro / 50 MB Boost, WhatsApp at 16 MB. HEVC's compression efficiency means a trimmed 30-60 second 1080p HEVC clip usually fits without further re-encoding.

For repackaging into a more universally playable container, see HEVC to MP4, HEVC to MOV, or Compress HEVC for size-only reduction without trimming.

Stream Copy vs Re-encode — When to Use Which

Property	Stream copy (default)	Re-encode
Speed	Seconds for any size, even 80 GB UHD remuxes	Proportional to clip length
Quality	Bit-identical to source HEVC	Slight loss unless CRF 18-20
Cut precision	Snaps to nearest keyframe (1-10s typical)	Frame-accurate
Output codec	Stays H.265 / HEVC	H.264, H.265, AV1, VP9, MPEG-4, etc.
HDR10 / HDR10+ / Dolby Vision	Preserved exactly	May strip unless explicitly carried
10-bit / 12-bit color depth	Preserved	Preserved if codec supports
Output size	Proportional to duration kept	Variable by CRF / bitrate
Best for	iPhone clips, UHD remuxes, HDR sources	Frame-accurate cuts, codec change for compatibility

Stream-copy can only cut on keyframes (I-frames). iPhone HEVC captures typically have a keyframe every 1-2 seconds, so the cut snaps within 1-2 seconds of your timestamp; UHD Blu-ray remuxes are similar. If you need the exact frame, enable re-encode and pick CRF 18-20 to keep the loss invisible.

HEVC Trim Quick Guide

Source	Typical GOP	Trim style	Notes
iPhone HEVC capture (iOS 11+)	1-2 sec	Stream copy	50% smaller than equivalent H.264
4K drone / action cam (DJI, GoPro)	1-2 sec	Stream copy	Preserves full 4K bitrate
UHD Blu-ray remux (HDR10 / DV)	1-2 sec	Stream copy	HDR metadata travels with the H.265 stream
IP-camera HEVC export	2-5 sec	Stream copy	Long GOPs from low-bitrate encoders
Raw .hevc annexb stream	1-5 sec	Stream copy	No container changes, output stays annexb
HEVC at 10-bit (Main10 profile)	1-2 sec	Stream copy	Preserved bit-perfect

Frequently Asked Questions

Will trimming my HEVC file lose any quality?

Not in the default stream-copy mode. XConvert writes the original H.265 bytes into a new HEVC output without decoding or re-encoding — the trimmed clip is bit-identical to that portion of the source. This matters for HEVC specifically because re-encoding it is slow (HEVC encoding is roughly 5-10× slower than H.264 at the same quality) and any re-encode introduces some loss. Quality only changes if you opt into re-encode to switch codecs, change resolution, or compress further; at CRF 18-20 the loss is visually imperceptible.

Will the trimmed HEVC play on my Windows PC?

Windows 10/11 doesn't include an HEVC decoder by default — Microsoft charges $0.99 for the "HEVC Video Extensions" codec from the Microsoft Store. Free workarounds: VLC, MPV, or PotPlayer all decode HEVC out of the box. If your audience is on Windows and you don't want to ask them to install anything, re-encode to H.264 in step 3 or run the trimmed file through HEVC to MP4 afterwards.

Will HDR10 and Dolby Vision metadata survive the trim?

Yes in stream-copy mode. HDR10 static metadata, HDR10+ dynamic metadata, and Dolby Vision RPU all travel inside the HEVC elementary stream — stream-copy doesn't touch the bytes, so the trimmed output plays back in HDR mode on the same TVs, Apple TVs, and Plex clients that handled the source. Re-encoding HDR HEVC is risky: most browser-based encoders strip Dolby Vision RPU or remap to SDR unless you explicitly carry the metadata, so for HDR sources stream copy is the safe default.

Why does the cut start a second or two off from where I set it?

Stream-copy can only cut on keyframes (I-frames). iPhone HEVC and most camera HEVC use a 1-2 second GOP, so the cut snaps to the nearest preceding keyframe — typically within 1-2 seconds of your requested timestamp. The first frame of the output has to be a keyframe so it decodes correctly. For frame-accurate cuts (the exact frame a goal lands, the precise word in a podcast), enable re-encode in step 3 and pick CRF 18-20.

Can I trim multiple HEVC clips with the same time range in one batch?

Yes. Drop in multiple HEVC files and the same start time + duration applies to each output — useful for trimming the same 5-second intro off a batch of episode files, or extracting the same window from multiple camera angles of one event. Per-file overrides are also supported if one clip needs a different range. All trimmed files come back as a ZIP.

What's the maximum HEVC file size I can trim?

There's no fixed cap. Trimming runs in your browser, so the practical limit is your device's available memory and patience for the upload. Multi-GB iPhone 4K captures and 50-80 GB UHD Blu-ray remuxes both work — competitors like online-video-cutter.com cap free uploads at 4 GB; XConvert does not. Stream-copy is fast enough that even an 80 GB UHD remux finishes in under a minute once loaded since no transcoding happens.

Can I trim a .hevc raw elementary stream (no container)?

Yes. Raw HEVC annexb streams from FFmpeg, screen recorders, or IP-camera exports are accepted directly — XConvert reads the NAL units, finds the keyframe before your start time, and writes a new annexb stream from there. The output stays as a raw .hevc stream; if you need it remuxed into MP4 or MKV after trimming, use HEVC to MP4 or HEVC to MKV in a second pass.

Will the audio stay in sync after trimming an iPhone HEVC clip?

Yes. iPhone HEVC captures store H.265 video alongside AAC audio in an MOV/MP4 container; stream-copy trim preserves both tracks aligned to the new start time. If you re-encoded the audio without specifying the same start offset you'd risk drift, but XConvert handles the timestamp realignment automatically. Slow-motion clips (which carry a metadata flag for the slow-mo region) also keep their audio sync through stream-copy.

Should I trim first or convert to MP4 first?

Trim first. Stream-copy trimming is essentially free (seconds) and shrinks the source from a multi-GB file down to whatever portion you actually want. Running HEVC to MP4 on a 4 GB capture is a much slower transcode than running it on a 200 MB trimmed clip — easily 5-10× faster end-to-end when the conversion involves H.265 → H.264 re-encoding for Windows compatibility.