Image Specs
Photo Post
| Dimensions | 540 × 810 px recommended; click-through version up to 2048 × 3072 px |
|---|---|
| Max File Size | 20 MB per image |
| File Formats | JPG, PNG, WEBP |
| Notes | Up to 30 photos per post on web (10 in the apps); RGB only; animated GIFs covered separately |
Animated GIF
| Dimensions | 540 px wide recommended |
|---|---|
| Max File Size | 10 MB |
| File Formats | GIF |
| Notes | GIFs over 3 MB are compressed and must end up 5 MB or smaller, otherwise only the first frame is shown; all GIFs are converted to GIFV |
Avatar
| Dimensions | 128 × 128 px (upload at 512 × 512 px for retina sharpness) |
|---|---|
| Max File Size | 10 MB |
| File Formats | JPG, PNG, WEBP |
| Notes | Displayed as a square with rounded corners; GIFs can be uploaded but are converted to a static image, so animated avatars are no longer supported |
Blog Header
| Dimensions | 2048 × 1152 px recommended (16:9) |
|---|---|
| Max File Size | 10 MB |
| File Formats | JPG, PNG, WEBP, GIF |
| Notes | Shown at the top of your blog; keep key content in the centre 1200×600 px safe zone — edges are cropped on many screen sizes |
[Ad]
Video Specs
Video Post
| Max File Size | 500 MB |
|---|---|
| File Formats | MP4, MOV |
| Resolution | Up to 1280 × 720 px recommended |
| Max Duration | Up to 10 minutes |
| Notes | H.264 + AAC recommended; one video per post, transcoded to 720p H.264 MP4; up to 20 videos and 60 minutes total per day; videos can also be embedded from YouTube, Vimeo, etc. |
Text & Character Limits
Text Post Body
| Character Limit | 4,096 characters per text block |
|---|---|
| Notes | Supports rich formatting; the 4,096-char limit applies per text block (longer paragraphs are split into multiple blocks); a post including its full reblog trail cannot exceed 524,288 characters |
Post Title
| Character Limit | 300 characters |
|---|
Quote Post
| Character Limit | 4,096 characters |
|---|
Tags
| Character Limit | 30 tags; 140 characters per tag |
|---|---|
| Notes | Tags are the primary discovery mechanism on Tumblr |
Blog Description / Bio
| Character Limit | 1,000 characters |
|---|
Blog Name (URL)
| Character Limit | 32 characters |
|---|---|
| Notes | Becomes yourblog.tumblr.com; lowercase letters, numbers, and hyphens |
Profile & Blog Assets
Avatar
| Dimensions | 128 × 128 px (upload at 512 × 512 px for retina sharpness) |
|---|---|
| Max File Size | 10 MB |
| File Formats | JPG, PNG, WEBP |
| Notes | Displayed as a square; GIFs can be uploaded but are converted to a static image, so animated avatars are no longer supported |
Blog Header
| Dimensions | 2048 × 1152 px recommended (16:9) |
|---|---|
| Max File Size | 10 MB |
| File Formats | JPG, PNG, WEBP, GIF |
Blaze Ads
Blaze Promoted Post (Image)
| Dimensions | Minimum 600 × 600 px |
|---|---|
| Aspect Ratio | 1:1, 4:3, or 16:9 |
| Max File Size | 5 MB |
| File Formats | JPG, PNG |
| Notes | Tumblr Blaze boosts an existing original post into other users' feeds; packages from $10 (~2,500 estimated audience) to $150 (~50,000); runs 24 hours by default; 18+ only |
Blaze Promoted Post (GIF)
| Dimensions | Minimum 600 × 600 px |
|---|---|
| Aspect Ratio | 1:1, 4:3, or 16:9 |
| Max File Size | 5 MB |
| File Formats | GIF |
| Notes | Animated GIFs allowed in Blaze promotions |
Blaze Promoted Post Title
| Character Limit | 300 characters |
|---|