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.
The things that get ads rejected.
clickTag
Confirms the exit/clickTag is present and set up the way the chosen ad server expects.
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.
Three steps, about ten seconds.
Upload your ZIP
Drag in the HTML5 banner ZIP. Nothing uploads to a server — it's parsed locally in your browser.
Read the report
See every check, the score and the verdict instantly — nothing held back. Free covers 2 banners a day — 5 with a free account.
Preview & fix
Watch the ad in a live preview and scrub its timeline, fix what's flagged, and re-check.
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 a scrubbable timeline 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.
HTML5 Ad QA vs Adloom and Google HTML5 Validator
Drop the ZIP and get 23 checks across 11 ad-server profiles — 13 read from the package, 10 measured from the ad as it runs — plus a replayable preview with a day/night backdrop, and a console and resource list, read entirely in your browser. Adloom does more, with 40+ checks and automatic fixes, at $49/month. Google’s free validator now shows “no longer maintained”, and it uploads your creative to a URL its own page warns is publicly accessible.
| HTML5 Ad QA | Adloom Starter | Google HTML5 Validator unmaintained | |
|---|---|---|---|
| Price | $1 per tool · $35/mo for all 39+ tools · Or $280/yr. No credits, no per‑use fees. | $49/mo flat monthly · 150 scans, 1 user, $0.25 overage | $0 |
| One tab of a 39-tool subscription — this validator isn't sold on its own | Yes · Free gets the complete report — nothing held back — for 2 a day with no account, 5 with a free one. PRO ($35/mo, $280/yr) removes the daily cap and adds the other 38 tools. Two of the three rivals here are free outright, so the bundle only saves you money if you want the rest of the suite. | No · $49/mo Starter buys this one product | standalone · $0 |
| Your ZIP and its contents never leave your machine | Yes · JSZip opens the archive locally and the preview inlines packaged assets as data: URIs, so the creative is never uploaded to us, never stored, and never given a shareable URL. | — · cloud product; not stated | No · its own page warns the uploaded creative is publicly accessible to anyone with the URL |
| No credits, no overage bill | Yes · Nothing is metered by credits and no run ever bills you extra. Free does carry a daily counter — 2 a day with no account, 5 with a free one, rolling over at midnight, with a repackage counting as one — and PRO removes it. Re-validating the same ad still spends a run. | 150 scans/mo · then $0.25 per extra scan; next tier up is $199/mo | — · free; publishes no scan cap |
| Plays the ad and catches its runtime console errors in the same pass | Yes · Replay and a scrubbable timeline, a night/day checkerboard backdrop, plus Details / Resources / Console tabs beside the report — and 10 runtime checks read from the ad while it plays. | — · not stated | — · bare pass/fail, no report |
| Border check reads the ad's actual rendered pixels | Yes · Beyond grepping the CSS it samples luminance rings on the rendered canvas and reports thickness and light/dark. Canvas-based ads (Animate/CreateJS) only — DOM/CSS banners get the CSS check alone, and it is warning-level, never a hard fail. | — · not stated | — · not stated |
| Repairs the package, not just the report | Yes · Every repair is listed and individually vetoable, your original ZIP is never touched, and the output is re-validated so the before/after score is measured rather than claimed: strips editor junk, drops unreferenced files, steps image quality down toward the profile’s weight cap, adds a clickTag declaration where none exists (additive only — existing click code is never rewritten) and can capture an end-frame backup JPG alongside. Formats and filenames are never changed, so recompression alone cannot always reach the cap. | Yes · advertises automatic fixes; the specifics are not itemised on their page | No · bare pass/fail, no report |
| Number of automated checks | 23 · 13 from the package (zip, primary HTML, assets present, weight, file count, click‑through present and wired, click URL, ad.size meta, HTTPS, naming, animation length, border) plus 10 measured from the ad as it runs: broken images, blank frame, text under 9px, copy clipped by its container, WCAG AA contrast, copy outside the frame, clickable surface and size, and real animation length. Across 11 ad‑server profiles. | 40+ · plus automatic fixes | — · not stated |
| Max ZIP accepted | 10 MB · Fine for a packaged display banner, but a real ceiling on video-bearing or rich-media packages. | — · not stated | — · not stated |
| Exportable or shareable report | Yes · Print/PDF, plus a plain‑text summary to paste into an email or ticket. No hosted share link. | Yes · PDF export on Starter | No · bare pass/fail, no report |
Prices checked 19 July 2026 from each vendor’s own pages. Adloom: $49/mo Starter, flat not per seat, monthly billing — its annual toggle advertises “Save 20%” but the discounted figure did not render for us; scans over 150/mo bill at $0.25 each, and the next tier up is $199/mo, so real spend can far exceed $49. Google’s validator is free and has no pricing page, but it is not a live product anymore: the tool displays “This tool is no longer maintained”, still carries pre‑2018 DoubleClick branding, deprecation was announced for April 2025, and the Campaign Manager 360 help article’s own link to it now 404s — so a pass there is no guarantee CM360 will accept the ZIP. It also uploads your creative and warns on its own page that the file becomes publicly accessible to anyone with the URL. Bannerflow was dropped deliberately: it is a creative‑production platform rather than a preflight validator and its pricing is quote‑only, so including it would flatter us unfairly. A grey “—” means the vendor does not publish that fact, not that the answer is no. Where we are weaker: Adloom runs more checks and will repair the ad for you; we only report. Our 10 runtime checks need the ad to render, so a creative that draws its copy into a <canvas> reports the text checks as skipped rather than passed. Weight and file limits outside Google Ads’ published 150 KB are our own sensible defaults, shown on screen so you can judge them, and the Adform and Flashtalking click‑convention patterns are written from documented behaviour rather than validated against a live export from each platform. Free covers 2 a day with no account, 5 with a free one, with nothing held back. None of them is affiliated with DigiLakshya.
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.
Quick answers.
Is the HTML5 ad validator really free?
Do my files get uploaded to a server?
What does it check?
Which ad platforms does it cover?
clickTAG, a Flashtalking myFT.applyClickTag() with its manifest.js (or a legacy ftClick) and a Studio/Sizmek Enabler.exit() are each judged correctly instead of all being measured against Google's clickTag. The Google Ads (600 KB, 40 files) and CM360 (10 MB) limits are Google's own published figures; Generic keeps the 150 KB initial-load budget most publisher specs enforce; the other profiles are our own sensible defaults, all shown on screen so you can judge them.Can you just build or fix the ad for me?
Do these tools use credits or tokens?
Validate your ad now — free.
Free to use with no signup, nothing uploaded — every check, the score and the verdict, with nothing held back — 2 banners a day, or 5 with a free account. 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.