Decision workspace

Compare your thumbnail before publishing

Upload your draft thumbnail, paste a few competing YouTube links, and see how your thumbnail reads in a feed before you publish.

Open extractor

Workspace signals

Local MVP
Local image preview1-10 public referencesCopy-ready decision summary

Three-step review

Put your draft beside the thumbnails viewers may see first

Everything in this MVP runs in the browser. Your uploaded thumbnail is not sent to GrabThumbs, and public references are generated from YouTube video IDs only.

Step 1

Upload my thumbnail

Use a JPG, PNG, GIF, or WebP draft. The preview stays local in your browser and is checked against current YouTube thumbnail guidance.

Upload best practice: 3840x2160, at least 640px wide, 16:9. YouTube Help lists JPG, GIF, and PNG; WebP is local preview only. 1280x720 is the 720p experiment floor.

Choose an image to see it pinned as the first feed card.

Your draft preview will appear here

Choose an image to see it pinned as the first feed card.

Spec warnings

Step 2

Paste competitor YouTube URLs

Add one URL per line. GrabThumbs uses only the video ID to build public reference thumbnail URLs.

Use 1 to 10 public YouTube or Shorts URLs. Duplicate IDs are ignored.

Reference

0

Step 3

Choose feed mode

Switch the board between wider desktop cards, compact mobile feed, and a vertical Shorts crop.

Feed preview

See the draft in a competitive row before you publish

The board is a decision aid, not a reuse license. Public thumbnails are shown only as references.

Reference only - do not reuse without permission.

Add your draft and at least one reference

Once both sides are present, the board makes mobile readability and visual difference easier to judge.

Decision checklist

Mark what still survives at feed size

These are manual judgment prompts. The tool does not score your thumbnail or claim a winner.

Export

Copy a decision summary for your upload notes

The summary includes mode, references, spec warnings, checklist decisions, YouTube A/B notes, Shorts/vertical caveats, and one recommended next action.

# Thumbnail decision summary

Date: 2026-06-14
Mode: Mobile feed
References: 0
Warnings:
- None
Checklist:
- Mobile readable: no
- Subject visible fast: no
- Different from references: no
- Text short enough: no
- Promise matches title: no
YouTube publishing notes:
- Native YouTube A/B testing is available in YouTube Studio on desktop, supports up to 3 title/thumbnail combinations, and selects winners by watch time share rather than CTR alone.
- Shorts are not eligible for native YouTube A/B testing, and Shorts do not support uploaded custom thumbnails like long-form videos. A frame may be selected for some Shorts surfaces, and it cannot be changed after upload.
- For vertical videos, a 16:9 custom thumbnail may be replaced by an auto-generated 4:5 thumbnail on mobile home, explore, and subscriptions surfaces.
Next action:
- Try stronger contrast, simpler text, or a clearer subject so the draft separates from references.

Summary is ready when you need it.

Packaging experiment

Turn this comparison into a 1-day test note

Add two or three variants, log early impressions, clicks, and watch time, then copy a directional recommendation without claiming statistical certainty.

Related next tools

Use this between reference extraction and packaging checks

After comparing the draft, continue into thumbnail test logging, title, thumbnail text, description, Shorts caption, and the full tools hub workflow.

Start here

Thumbnail Extractor

Open a real public YouTube or Shorts thumbnail first, then use it as the reference for the rest of the packaging review.

Open extractor

Live now

Competitor Thumbnail Board

Group public reference thumbnails, pin your own draft, add manual pattern tags, and export the local board.

Build board

Live now

Frame Hunter

Sample local video frames in the browser and export a 1280x720 candidate before comparing the thumbnail direction.

Find frames

Live now

Thumbnail Test Flow

Plan up to three thumbnail variants, log CTR and watch time share, and export a conservative local decision note.

Log test

Live now

YouTube Title Checker

Check whether the video title carries the same promise as the thumbnail and still fits mobile preview cuts.

Check title

Live now

Thumbnail Text Checker

Review thumbnail wording for mobile readability, density, and whether it adds a different job from the title.

Check text

Live now

YouTube Description Formatter

Clean the publish description so the opening, links, CTA, chapters, and hashtags support the same click promise.

Format description

Live now

Shorts Caption Formatter

Tighten short-form hooks, CTA lines, and hashtag blocks when the video idea is reused for Shorts.

Format caption

Hub

Creator Tools Hub

See the eight live tools, the extractor-first workflow, and the guide paths that support each step.

Open tools hub

Related guides

Read the strategy behind the comparison

These guides help you judge contrast, audience fit, CTR repair, and reference boundaries after the board surfaces a problem.

Guide

3 fundamentals that make YouTube thumbnails easier to click

A lot of thumbnail improvement comes from boring basics done well: contrast, compression, and a clear emotional cue.

Read guide

Guide

How thumbnail design changes when your audience changes

Different age groups often respond to different levels of visual density, but your own audience data should lead the way.

Read guide

Guide

YouTube Thumbnail Color Combinations: Contrast Examples for 2026

Use practical YouTube thumbnail color examples to keep subjects readable, separate foreground from background, and avoid palettes that disappear in the feed.

Read guide

Guide

Can You Reuse YouTube Thumbnails? Copyright Boundaries for Creators

Use a practical copyright-risk checklist for YouTube thumbnail research, reference boards, fair-use questions, and original thumbnail rebuilds.

Read guide

FAQ

Questions about thumbnail comparison

Does this upload my thumbnail to GrabThumbs?

No. The uploaded image is previewed with a local browser object URL and is not sent to a server in this MVP.

Can I reuse competitor thumbnails from this board?

No. Public thumbnails are shown as references for comparison only. Do not reuse them without permission.

Why does this not automatically search competitors by keyword?

The MVP avoids the YouTube Data API and its quota costs. Pasting a few known references keeps the tool free and predictable.

Does this use AI to score the winner?

No. This version gives you a realistic board, manual checks, and a copyable decision summary rather than AI scoring.