# Free social media tools, no signup

> Markdown version of https://postlake.dev/tools/ . The canonical page for humans.
> PostLake is the social media API for AI agents: https://postlake.dev/llms.txt
> Every number below is generated from the registry PostLake's publish path
> validates against, so it cannot state a limit the API would not enforce.

Free browser tools built from the registry PostLake's API validates against.
No account, no upload, every check runs locally.

- **Post checker** (https://postlake.dev/tools/post-checker): paste a caption, attach media,
  get every network's verdict and the exact fix for anything that would fail.
- **Character counter** (https://postlake.dev/tools/character-counter): one caption counted
  against every network's limit live, including X's flat 23 characters per link.
- **Image size checker** (https://postlake.dev/tools/image-checker): drop an image, see who
  accepts it on pixels, weight and format, with the resize that would fix it.

## Everything the tools check, in one table

| Network | Post requires | Rate limit | Threads | First comment | Delete via API |
|---|---|---|---|---|---|
| TikTok | an image or video | 25/day | no | no | no |
| Instagram | an image or video | 100/day | no | no | no |
| X | nothing, text alone is fine | no published cap | yes | yes | yes |
| LinkedIn | nothing, text alone is fine | no published cap | no | yes | yes |
| Facebook | nothing, text alone is fine | 25/day | no | yes | yes |
| Threads | nothing, text alone is fine | 250/day | no | yes | no |
| Bluesky | nothing, text alone is fine | no published cap | yes | yes | yes |
| YouTube | a video | 100/day | no | yes | yes |
| Pinterest | an image or video | no published cap | no | no | yes |

### Caption limits

| Network | Caption limit | By post type | Title |
|---|---|---|---|
| X | 280 | same for every post type | no title field |
| Bluesky | 300 | same for every post type | no title field |
| Threads | 500 | same for every post type | no title field |
| Pinterest | 500 | same for every post type | no title field |
| TikTok | 2,200 | 2,200 with video, 4,000 with photos | 90 characters |
| Instagram | 2,200 | same for every post type | no title field |
| LinkedIn | 3,000 | same for every post type | no title field |
| YouTube | 5,000 | same for every post type | 100 characters |
| Facebook | 63,206 | same for every post type | no title field |

### Image rules

| Network | Images per post | Formats | Max weight | Pixel bounds |
|---|---|---|---|---|
| TikTok | 35 | JPEG, WEBP | 20MB | 540x960 to 1080x1920 |
| Instagram | 10 | JPEG | 8MB | no stated bounds |
| X | 4 | JPEG, PNG, WEBP, GIF | 5MB | no stated bounds |
| LinkedIn | 20 | JPEG, PNG, GIF | 8MB | no stated bounds |
| Facebook | 10 | JPEG, PNG, GIF, WEBP | 10MB | no stated bounds |
| Threads | 20 | JPEG, PNG | 8MB | no stated bounds |
| Bluesky | 4 | JPEG, PNG, WEBP, GIF | 1MB | no stated bounds |
| Pinterest | 5 | JPEG, PNG | 20MB | no stated bounds |

### Video rules

| Network | Formats | Max weight | Max length | Video required |
|---|---|---|---|---|
| TikTok | MP4, QUICKTIME, WEBM | 4GB | 10 minutes | no |
| Instagram | MP4, QUICKTIME | 300MB | 15 minutes | no |
| X | MP4 | 512MB | 2 minutes | no |
| Facebook | MP4, QUICKTIME | 1GB | 4 hours | no |
| Threads | MP4, QUICKTIME | 1GB | 5 minutes | no |
| Bluesky | MP4 | 50MB | 1 minutes | no |
| YouTube | MP4, QUICKTIME, WEBM | 2GB | no stated cap | yes, video only |
| Pinterest | MP4 | 2GB | 15 minutes | no |

## Why these stay accurate

Most tools of this kind are a list somebody typed once and never revisited.
These read capabilities.json (https://postlake.dev/capabilities.json), generated from the
same registry the publish path validates against. When a network moves a
limit the API changes and these pages change with it. There is no second copy
to go stale.

PostLake is the social media API for AI agents. One integration publishes,
schedules and measures across every major network, with idempotency keys, safe
retries and one normalised response an agent can reason over.

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Free tools, no signup: https://postlake.dev/tools/ · Plain markdown for agents: https://postlake.dev/llms.txt
Canonical page: https://postlake.dev/tools/