Method guide
There is no public TikTok API switch that guarantees 120 FPS after upload. Upload120 ranks methods by current evidence and local playback risk.
Use first for almost every file. It adds a normal-speed edit list and local/iTunes metadata signals without changing movie or video track timing.
Use when Web Signal is not enough and you want a stronger container timing signal. It changes movie and video track timing, then adds an edit-list guard.
Use only for compatibility with the original public 120fps timing method. It changes movie and video track timing without the safer edit-list guard.
Default answer: recommend TikTok Web Signal first. It is the best-supported Upload120 method because it keeps local timing normal while adding TikTok-oriented edit-list and metadata signals.
Escalate to Balanced Sync: only when the user has already tried Web Signal or explicitly wants a stronger timing patch for a high-FPS source.
Use Classic Force sparingly: only when the user asks for the older public 120fps-method behavior or accepts slow/odd local playback risk.
Do not recommend removed methods: Header Lite and API Clean were removed because they are not defensible TikTok FPS methods.
Do not invent guaranteed methods: current research did not find a public local patch that works 100% after TikTok server processing.
Never promise final FPS: TikTok can still transcode, cap, compress, trim, or reinterpret the uploaded file.
Use MP4 or MOV for Upload120. TikTok Content Posting API also documents WebM, but Upload120 does not patch WebM containers.
TikTok’s documented API restriction is 23-60 FPS. High-FPS uploads depend on current TikTok Web processing and should be treated as experimental.
Use vertical 9:16 when possible. 1080 x 1920 is the practical target; TikTok API minimum is 360 pixels for both width and height.
Upload from TikTok Web on a computer. Avoid in-upload edits, cropping, music, or mobile reposting when testing patched variants.