Free to use · No signup to preview · Runs in your browser

Free HTML5 Banner Ad Validator

Drop in your HTML5 ad ZIP and get 23 checks in seconds across 11 ad-server profiles — click-through setup, weight, animation length, contrast and clipped copy — with a live, replayable preview. Catch the issues before trafficking does.

Launch the validator How it works
Your files never leave your browser — safe for unreleased campaigns.
What it checks

The things that get ads rejected.

clickTag

Confirms the exit/clickTag is present and set up the way ad servers expect — the clickTag detail unlocks with a free login.

File weight

Flags total ZIP and initial-load weight against standard size budgets.

Animation length

Checks the animation duration against platform limits so loops don't get rejected.

Borders & more

Border requirements and other common CM360 checks, with clear warnings.

How it works

Three steps, about ten seconds.

1

Upload your ZIP

Drag in the HTML5 banner ZIP. Nothing uploads to a server — it's parsed locally in your browser.

2

Read the report

See every check, the score and the verdict instantly — nothing held back. Free covers 5 banners a day.

3

Preview & fix

Watch the ad in a live preview with replay/pause, fix what's flagged, and re-check.

Why use it

Built by people who traffic ads all day.

Private by design

Validation runs entirely in-browser. Your creative never leaves your machine.

See it run

A live preview with timer and replay, so you catch visual issues a spec check can't.

Real production knowledge

From a studio that builds 1,000+ trafficking-ready units a month for agencies.

Prefer it built right the first time?

We build trafficking-ready HTML5 banners for agencies.

Skip the validate-fix-revalidate loop. Send us the design and get DV360/CM360-ready units, white-label, with a free first sample.

DV360 banner production
FAQ

Quick answers.

Is the HTML5 ad validator really free?
Yes. Every check, the score and the verdict are free with no signup — nothing is held back. Free use is capped at 5 banners a day; PRO ($25/month) lifts the cap and adds the other 25 tools.
Do my files get uploaded to a server?
No. The validation runs entirely in your browser — your creative never leaves your machine, so it's safe for unreleased campaigns.
What does it check?
23 in total. 13 package checks read from the ZIP — click-through setup, file size and count, animation length, borders, missing assets, the ad.size meta tag, HTTPS/mixed-content and file/reference naming — plus 10 runtime checks measured from the ad while it actually runs in the preview: broken images, a blank frame, text under 9px, copy clipped by its container, WCAG AA contrast, copy pushed outside the ad, whether a clickable surface exists and is big enough, and the real animation length. Not every runtime check applies to every ad — a creative that draws its copy into a <canvas> reports the text checks as skipped rather than passed.
Which ad platforms does it cover?
Pick from 11 trafficking profiles: Generic, Google Ads, Campaign Manager 360, Display & Video 360, Adform, Flashtalking, Amazon Ad Server (Sizmek), Xandr, The Trade Desk, Equativ and a strict IAB-style profile. Each applies its own limits and — the part that matters — its own click-through convention, so an Adform clickTAG, a Flashtalking ftClick and a Studio/Sizmek Enabler.exit() are each judged correctly instead of all being measured against Google's clickTag. Weight and file limits outside Google Ads' published 150 KB are our own sensible defaults, shown on screen so you can judge them.
Can you just build or fix the ad for me?
Yes — that's our day job. We produce trafficking-ready HTML5 banners for agencies. See DV360 banner production or send us a brief for a free sample build.
Do these tools use credits or tokens?
No — never. Every tool is free to use with sample or daily limits, and PRO is a flat $25/month ($199/year) for unlimited use of all 25+ tools: no credit packs, no top-ups, no per-use fees. Many comparable tools bill per credit (remove.bg, CloudConvert, AdCreative.ai) — here one flat subscription covers everything. See tools pricing.

Validate your ad now — free.

Free to use with no signup, nothing uploaded — every check, the score and the verdict, with nothing held back, for 5 banners a day. It will also repackage the ad for you: strip editor junk, drop unreferenced files, recompress images toward the platform’s weight cap and add a clickTag declaration if one is missing, then re-validate the result so the improvement is proven. Check your HTML5 banner against CM360 specs in seconds, or hand the build to us.

Launch the validator Get a free sample build