iTechGuides is reader-supported. When you buy through links on our site, we may earn an affiliate commission. As an Amazon Associate I earn from qualifying purchases. Learn more
In a September 2026 re-probe of 1,000 YouTube videos, WebP maxresdefault thumbnails at 1280×720 had about half the median bytes of their JPEG counterparts. At 480×360, the result was less consistent: WebP was larger in one-third of paired files overall and in 72% of the sampled 2026 uploads. These are file-size findings, not image-quality results.
Are YouTube WebP thumbnails smaller than JPEG?
Usually in the larger thumbnail tiers in this sample, but not reliably at the smaller 480×360 tier. Thumbnails Grabber’s 2026 study re-probed 1,000 public videos, measuring WebP files on September 19 and the corresponding JPEG files on September 7. The table reports medians for videos where both formats existed; the ratio is the median of the paired per-video WebP/JPEG ratios, not a division of the two median sizes.
| Thumbnail variant | Dimensions stated by study | Median JPEG | Median WebP | Median paired WebP/JPEG ratio | Pairs where WebP was larger |
|---|---|---|---|---|---|
maxresdefault |
1280×720 | 96.7 KB | 50.8 KB | 0.53 | 10 of 965 (1.0%) |
sddefault |
640×480 | 41.3 KB | 23.3 KB | 0.55 | 14 of 970 (1.4%) |
hqdefault |
480×360 | 19.0 KB | 15.6 KB | 0.75 | 324 of 970 (33.4%) |
At 1280×720, the median WebP file was 45.9 KB smaller than the median JPEG, and WebP was smaller in 955 of the 965 pairs with both files. Across those pairs, all WebP bytes summed to 59.1% of all JPEG bytes. The 640×480 results were similar in aggregate: WebP bytes summed to 59.5% of JPEG bytes across the 970 pairs.
Recommended Free Tools
The byte gap at 480×360 was narrower. Its overall median ratio was 0.75, but WebP exceeded JPEG in 324 of 970 pairs. So “WebP is always smaller” is not a safe rule for every YouTube thumbnail size.
#1 Best Overall
- CRISP CLARITY: This 23.8″ Philips V line monitor delivers crisp Full HD 1920x1080 visuals. Enjoy movies, shows and videos with remarkable detail
- INCREDIBLE CONTRAST: The VA panel produces brighter whites and deeper blacks. You get true-to-life images and more gradients with 16.7 million colors
- THE PERFECT VIEW: The 178/178 degree extra wide viewing angle prevents the shifting of colors when viewed from an offset angle, so you always get consistent colors
- WORK SEAMLESSLY: This sleek monitor is virtually bezel-free on three sides, so the screen looks even bigger for the viewer. This minimalistic design also allows for seamless multi-monitor setups that enhance your workflow and boost productivity
- A BETTER READING EXPERIENCE: For busy office workers, EasyRead mode provides a more paper-like experience for when viewing lengthy documents
Why can a 480×360 WebP thumbnail be bigger than JPG?
The study does not establish the cause. Its 480×360 result varies substantially by video cohort, and the format names alone do not predict the size of each separately encoded file.
Upload era changes the observed result
For the older-skewing Wikidata-referenced videos in the sample, the median 480×360 WebP/JPEG ratio was 0.65, and WebP was larger in 10.4% of pairs. For recent uploads, the median ratio was 1.06 and WebP was larger in 56.1% of pairs. Within the recent-upload subset, 2026 uploads (217 videos) had a median ratio of 1.13; WebP was larger in 72% of those comparisons.
Rank #2
- CRISP CLARITY: This 22 inch class (21.5″ viewable) Philips V line monitor delivers crisp Full HD 1920x1080 visuals. Enjoy movies, shows and videos with remarkable detail
- 100HZ FAST REFRESH RATE: 100Hz brings your favorite movies and video games to life. Stream, binge, and play effortlessly
- SMOOTH ACTION WITH ADAPTIVE-SYNC: Adaptive-Sync technology ensures fluid action sequences and rapid response time. Every frame will be rendered smoothly with crystal clarity and without stutter
- INCREDIBLE CONTRAST: The VA panel produces brighter whites and deeper blacks. You get true-to-life images and more gradients with 16.7 million colors
- THE PERFECT VIEW: The 178/178 degree extra wide viewing angle prevents the shifting of colors when viewed from an offset angle, so you always get consistent colors
Shorts show another distinct pattern
Among the 116 vertical Shorts in the study’s 480×360 subset, WebP was larger in 85.3% of pairs. In that Shorts subset’s maxresdefault results, however, the median WebP/JPEG ratio was 0.40. The tier and video cohort both matter; the small-thumbnail finding should not be generalized to all variants.
What the measurements do—and do not—show
The study compares bytes from public YouTube thumbnail URLs; it does not test whether the images look equally good. The JPEG and WebP files are separate encodes, and YouTube’s encoder settings are unpublished. A smaller file therefore does not prove equal or better visual quality.
Rank #3
- Clear visuals. Fluid motion: A 144Hz refresh rate and 1ms MPRT deliver smooth, tear‑free motion across work, gaming, and streaming for clearer, more fluid viewing.
- Eye comfort: TÜV Rheinland 3‑star* certification reduces harmful blue light while preserving stunning color quality without compromise. *TÜV Rheinland 3-star eye comfort certification.
- Wide viewing angle: Get consistent views across a wide 178° /178° viewing angle.
- In-Plane Switching (IPS): See excellent color accuracy and consistency across wide viewing angles with In-plane Switching (IPS) technology.
- Ultra-thin bezels: Maximize your viewing experience with thin bezels.
- The re-probe included 1,000 videos selected from 500 recent uploads and 500 Wikidata-referenced videos. It required a JPEG
maxresdefaultfile, so it is not a census of YouTube videos. - JPEG and WebP bytes were measured twelve days apart. If a thumbnail changed or was replaced between those dates, the compared files may represent different frames.
- The source reports 3,000 requests and zero errors for the re-probe, but did not decode WebP dimensions.
- Public CDN file availability and byte sizes can change when thumbnails are updated or reprocessed; these measurements describe the dates collected, not a permanent property of every thumbnail.
A separate 300-video study fetched on August 31, 2026, also found a smaller median WebP maxresdefault payload: 60,345 bytes versus 141,111 bytes for JPEG, or 57.2% smaller by the reported medians. Its IDs were curated rather than randomly selected from all uploads, so it supports the direction of the larger-thumbnail result without making it universal.
What this means if you use YouTube thumbnails on a site
For a page using a 1280×720 thumbnail, the sampled WebP files generally transferred fewer bytes than the paired JPEGs. For a 480×360 thumbnail, check the actual file and the relevant upload cohort rather than assuming WebP saves bandwidth. Compare the bytes users will receive, confirm the intended variant and dimensions, and assess visual quality separately.
Rank #4
- CURVED FOR ENHANCED ENGAGEMENT: An immersive viewing experience with a curved monitor that wraps more closely around your field of vision; It creates a wider view, enhancing depth perception and minimizing peripheral distraction
- SMOOTH PERFORMANCE FOR SEAMLESS CONTENT: Stay in the action when playing games, watching videos, or working on creative projects; The 100Hz refresh rate reduces lag and motion blur so you don't miss a thing in fast-paced moments¹
- MORE GAMING POWER: Gain the edge with optimizable game settings; Color and image contrast can be adjusted to see scenes more vividly and spot enemies hiding in the dark; Game Mode adjusts any game to fill the screen so you can view every detail²
- KEEP IT EASY ON THE EYES: Care for your eyes and stay comfortable, even during long sessions; Advanced eye comfort technology certified by TÜV reduces eye strain by minimizing blue light and reducing irritating screen flicker²
- INCREASED VERSATILITY: Connect to more; Plug devices straight into your monitor for increased flexibility, making your computing environment even more convenient
If you serve a format-specific asset, account for availability and fallback behavior: this study only compared pairs where both files existed. It does not establish that every video has a usable WebP at every tier, or specify how a site should construct thumbnail URLs.
Free tools Windows power users keep installed
One-click scans. No signup required.
Are these the same formats creators upload?
No. The study measured public CDN derivatives, not creator-upload files. YouTube Help recommends JPG or PNG among the formats for custom thumbnail uploads and says, “Your custom thumbnail image should be as large as possible.” Its upload guidance is separate from how YouTube later encodes public thumbnail variants. See YouTube Help: Add custom thumbnails on YouTube.
Best Value
- 【INTEGRATED SPEAKERS】Whether you're at work or in the midst of an intense gaming session, our built-in speakers provide rich and seamless audio, all while keeping your desk clutter-free.
- 【EASY ON THE EYES】 Protect your eyes and enhance your comfort with Blue-Light Shift technology. This feature reduces harmful blue light emissions from your screen, helping to alleviate eye strain during long hours of use and promoting healthier viewing habits.
- 【WIDEN YOUR PERSPECTIVE】Our sleek minimal bezel design ensures undivided attention. The nearly bezel-free display seamlessly connects in a dual monitor arrangement, delivering an unobstructed view that lets you focus on more at once, completely distraction-free.
WebP itself supports lossy and lossless compression, transparency, metadata, color profiles, and animation, and its specification describes it as optimized for fast image transfer over networks. Those format capabilities do not determine how YouTube’s separate encodes compare for a particular thumbnail. See RFC 9649: WebP Image Format.
Quick Recap
Sources and scope
- Thumbnails Grabber, “YouTube Thumbnail Statistics 2026: Data From 8,664 Videos” — includes the 1,000-video re-probe collected September 7 and 19, 2026.
- RFC Editor / IETF, RFC 9649, “WebP Image Format” — published November 2024.
- YouTube Help, “Add custom thumbnails on YouTube” — accessed October 7, 2026.
- Google for Developers, “Comparative Study: WebP” — September 2010, a historical study that labels itself as an initial comparison and notes that a newer study supersedes it.
- 11tik, “YouTube Thumbnail Sizes & Resolutions: 300-Video Study” — separate 300-video sample fetched August 31, 2026.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
