Instagram Reels caption limit: 2,200 characters, 30 hashtags

A Reels caption can be up to 2,200 characters, with at most 30 hashtags and 20 @ tags, according to Meta's Instagram Graph API page for publishing media. That is the text under the Reel, set with the caption field, and it is separate from any words drawn onto the video itself.

If you meant on-screen text, that is a different job: Sume burns captions into the video pixels. Both are covered below, with values read on 2026-09-29.

What are the caption limits on Meta's page?

The POST /<IG_ID>/media reference lists the caption field for Reels with the limits below. It also lists trial reels (graduation_strategy, MANUAL or SS_PERFORMANCE) and share_to_feed.

Is the post caption the same as burned-in captions?

No. The post caption is text stored by Instagram and shown under the Reel. Burned-in captions are part of the video image. Sume's POST /v1/video-captions makes the second kind: it transcribes speech, or uses your script_text, words or cues, and returns a new video with captions drawn in. It does not write or publish your Instagram caption.

A standalone caption job is a fixed $0.20 for videos up to 60 seconds, per the docs. SRT upload is unsupported; pass phrase-level cues instead.

curl -X POST https://api.sume.com/v1/video-captions \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: reel-caption-001" \
  -d '{
    "video_url": "https://media.sume.com/artifacts/example/clean.mp4",
    "style": "tiktok-green",
    "language": "en"
  }'

What about silent clips?

A generated clip with no speech fails with caption_no_speech if you rely on transcription. Send cues (timed phrases) instead, and use the design overrides such as placement.anchor_ratio to move the line up the frame, away from the bottom edge where app buttons and the post caption sit.

What are the limits of this answer?

Sume does not touch the Instagram caption field, hashtags or mentions. Limits above are Meta's and can change; re-read the page before you automate publishing.