Xvid to FLV

How to Convert Xvid to FLV Online

1. Upload Your Xvid File: Drag and drop your Xvid-encoded video onto the upload area or click "+ Add Files." Xvid is an MPEG-4 ASP codec usually wrapped in an AVI container, so files commonly arrive with .avi or .xvid extensions. Batch upload is supported for converting an entire archive in one pass.
2. Pick a Quality Preset: Open Advanced Options and choose a Quality Preset (Highest, Very High, High, Medium, Low, Lowest). Default is Very High. For thinner FLV streams suitable for legacy Flash players, switch to Constant Bitrate or Variable Bitrate, set Specific file size, or use Constant Quality (CRF) for a quality-locked output. Constraint Quality lets you cap the maximum quality while keeping bitrate flexible.
3. Resize or Trim (Optional): Under Video Resolution, keep original, pick a preset (240p, 360p, 480p, 720p, 1080p), enter exact Width x Height, or scale by Resolution Percentage. Under Trim, switch from Unchanged to Time Range and enter a start time and duration to extract a clip rather than re-encoding the whole file.
4. Convert and Download: Click Convert. Files are uploaded over an encrypted connection, processed on our servers, and deleted automatically after a few hours — no sign-up, no watermark, never shared. Output FLV files use the H.264 video / AAC audio profile that Flash Player 9.0.115.0 (December 2007) and later understand, so they remain compatible with the broadest set of legacy Flash players.

Why Convert Xvid to FLV?

Xvid (released 2001 under GPL v2) is an MPEG-4 Part 2 Advanced Simple Profile codec — the open-source counterpart to DivX — typically wrapped inside .avi containers. FLV (Flash Video, introduced by Macromedia/Adobe on September 10, 2003) is the legacy Flash streaming container that dominated web video from roughly 2005 to 2015, before MP4 with H.264 took over. Adobe ended support for Flash Player on December 31, 2020 and blocked Flash content from running on January 12, 2021, so FLV is now strictly a legacy format. People still need this conversion in a handful of well-defined situations:

• Legacy LMS and CMS systems — older Moodle, Blackboard, Joomla, and custom intranet platforms built around Flash-based players still expect FLV ingest. Replacing the player is a budget item; converting source video is not.
• Archival ingest pipelines — institutional archives (libraries, broadcasters, government departments) sometimes mandate FLV alongside the original AVI/Xvid for digital-preservation reasons, since the FLV is what the contemporaneous web actually served.
• RTMP streaming to legacy hardware — some closed-circuit signage, hotel IPTV, and corporate video walls still run firmware that ingests FLV over RTMP. New hardware speaks HLS/DASH; FLV keeps the old units running.
• Compatibility with Adobe Animate / Adobe Media Encoder pipelines — internal motion-graphics teams maintaining old Flash projects (.fla) will source video as FLV so the project's import path stays valid.
• Forensic and discovery work — recreating a website "as it was" for a legal matter often means matching the exact format originally served, including FLV.

For modern playback in a browser, on a phone, or on a smart TV, Xvid to MP4 is the better target — Flash is dead, MP4 is universal.

Xvid vs FLV — Format Comparison

FLV Output Codec Quick Guide

FLV is a container, not a codec. The video codec inside the FLV determines how universally it plays on legacy Flash builds.

If your target player is Flash Player 9 or newer (essentially every Flash install from 2008 onward), H.264 is the right pick. If you're feeding a very old Flash 6 or 7 runtime — for example, a Flash 7-era e-learning module that won't be updated — Sorenson Spark is the safer choice; xconvert's FLV output uses H.264 by default.

Frequently Asked Questions

Why does my Xvid file have an.avi extension instead of.xvid?

Xvid is a codec, not a container, so it is almost always packaged inside an AVI (.avi) file alongside an MP3 or AC3 audio track. The .xvid extension exists but is uncommon — it just signals that AVI's video stream uses the Xvid codec. xconvert accepts both extensions and treats them identically.

Will the converted FLV play in a modern browser?

No. Adobe ended Flash Player support on December 31, 2020, and blocked Flash content from running starting January 12, 2021. Chrome, Firefox, Edge, and Safari all removed Flash entirely. If you need browser playback, convert to Xvid to MP4 instead — MP4 with H.264/AAC plays in every modern browser without a plugin.

Should I pick H.264, VP6, or Sorenson Spark inside FLV?

H.264 (the xconvert default) is right for any Flash Player from version 9.0.115.0 (December 2007) onward — that covers essentially every Flash deployment from 2008 to the 2020 EOL. VP6 is the safer fallback for Flash 8 (2005) targets, and Sorenson Spark (FLV1) is only worth picking when your target is a very old Flash 6 or Flash 7 runtime that won't be updated.

Is FLV the same as F4V?

No. F4V was introduced by Adobe in 2007 and is based on the ISO base media file format (the same family as MP4), while the original FLV format dates from 2003 and uses a streaming-oriented tag structure. F4V supports H.264 and AAC more cleanly, but FLV remains what most legacy Flash CMS ingest pipelines expect. If your target system asks for "Flash Video," it almost always means .flv, not .f4v.

Will converting Xvid to FLV lose quality?

Yes — both formats use lossy compression, so a re-encode from Xvid (MPEG-4 Part 2) to FLV (H.264, VP6, or Sorenson Spark) always introduces some generation loss. Pick Highest or Very High under Quality Preset, or use Constant Quality (CRF) with a low value, to keep the loss visually negligible. There is no "copy stream" path for Xvid into FLV because FLV does not accept MPEG-4 Part 2 video.

Can I trim and resize in the same pass?

Yes. Under Trim choose Time Range and set start + duration; under Video Resolution choose a preset (480p is a common sweet spot for legacy Flash players) or enter custom Width x Height. Both transformations apply during the single re-encode, so you only pay the compression-loss cost once.

What is the maximum file size I can convert?

XConvert processes files on its servers and deletes them automatically after a few hours. Practical limits are determined by upload size and connection speed and tab memory rather than a hard server-side ceiling. For very large files, trim first if you only need a clip, or split the conversion across multiple sessions.

How do I batch-convert a folder of Xvid AVIs?

Drag the entire folder onto the upload area, or click "+ Add Files" and multi-select. Each file converts with the same Advanced Options settings, which is the right behavior when migrating a uniform archive (same source resolution, same target FLV profile). For per-file resolution differences, run them in separate batches.

What if I want a smaller FLV than the source AVI?

Use the Specific file size option under File Compression to set an exact target (for example, 50 MB), or set Target file size as a percentage of the source. You can also drop the resolution to 480p or 360p — FLV was originally designed for sub-720p web playback, so going below 480p rarely costs much perceptual quality and significantly shrinks the file. After conversion, Compress FLV can shrink an existing FLV further without changing format.