LinkedIn video ad intro text 150 characters, headline 70: test copy

For a LinkedIn video ad, the introductory text is limited to 150 characters (3,000 maximum) and the video headline to 70 (200 maximum), per LinkedIn's video ad specifications. Those words live in the ad, not in the video file, so you can test copy variants on one rendered clip. Spend Sume jobs on the things that change the file: a different hook, ratio or length.

That also tells you when a bulk run is worth queueing. A copy test needs no queue; a hook test does.

Text limits that apply to the ad

Check copy before you paste it

A small checker catches an over-long line before Campaign Manager truncates it. The 150 and 70 figures are the shown-length limits on the page; the larger maximums are what the field accepts.

LIMITS = {"intro": 150, "headline": 70, "name": 255}

def over(copy: dict) -> dict:
    return {k: len(v) - LIMITS[k] for k, v in copy.items() if len(v) > LIMITS[k]}

variants = [
    {"name": "q4-hook-a", "intro": "Cut weekly reporting from hours to minutes.", "headline": "See the 2-minute demo"},
    {"name": "q4-hook-b", "intro": "x" * 160, "headline": "Reporting, finished"},
]
for v in variants:
    print(v["name"], over({k: v[k] for k in LIMITS if k in v}) or "ok")

When a Sume job is worth it

The clip itself must meet the same page's file rules: MP4, 75 KB to 500 MB, 3 seconds to 30 minutes, and under 30 FPS. LinkedIn also states that videos under 30 seconds loop until there are at least 30 seconds of playback, and recommends 15 to 30 seconds.

• New hook or first three seconds: new clip, so a Sume job.
• New ratio: new clip, so a Sume job.
• New intro text or headline: no clip change, edit the ad only.