Guides
Practical how-tos for image sizes, file conversion, and developer workflows each linked to a free ToolKits tool.
109 guides · page 1 of 5
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Resize Image for Instagram
Instagram feed posts display best at 1080×1080 pixels for square posts. Uploading oversized photos slows posting and may get compressed unpredictably.
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Resize Image for YouTube Thumbnail
YouTube recommends 1280×720 pixels (16:9) for custom thumbnails. This size looks sharp on all devices and meets platform requirements.
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Resize Image for LinkedIn Banner
A professional LinkedIn banner is 1584×396 pixels. Crop or resize your image to this wide format for the best result.
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Resize Image for Twitter/X Header
X profile headers display at 1500×500 pixels on desktop. Resize your image to this ratio before uploading.
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Resize Image for Facebook Cover
Facebook cover photos are 820×312 pixels on desktop. Mobile crops differently keep key content centered.
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Resize Image for TikTok Cover
TikTok uses a 9:16 vertical format. For cover and story-style assets, 1080×1920 is the standard full-screen size.
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Resize Image for Discord Emoji
Discord recommends 128×128 pixels for custom emojis. Square, simple images work best at small sizes.
Conversion
JPG to PNG Online Free
Convert JPEG photos to PNG when you need lossless storage or transparency support in downstream editing.
Conversion
JSON to CSV for Excel
Excel opens CSV natively. Convert JSON arrays from APIs into spreadsheet-ready CSV in seconds.
Developer
Markdown to HTML Live Preview
Preview Markdown rendering before publishing to GitHub, a static site, or your CMS.
Developer
SQL Formatter Pretty Print
Formatted SQL is easier to review in pull requests, documentation, and debugging sessions.
Developer
Cron Expression Every 5 Minutes
The cron expression */5 * * * * runs a job every 5 minutes. Use our generator for other schedules too.
Conversion
WebP to JPG Online Free
WebP saves bandwidth but many apps only accept JPG. Convert locally without sending files to a server.
Developer
JSON Formatter vs Validator
Formatting makes JSON readable; validation checks if it is syntactically correct. You often need both.
Developer
What Is a Unix Timestamp
APIs and databases often store dates as Unix time a single integer counting seconds (or milliseconds) from the epoch.
Developer
robots.txt for Next.js
Next.js can serve robots.txt from app/robots.ts or public/robots.txt. Our generator helps you draft rules quickly.
Developer
Diff Checker for Code
Before committing, compare two versions of config, JSON, or source code to see exactly what changed.
Developer
JWT Generator for Testing
When building APIs, you need sample JWTs to test auth middleware. Generate HS256 tokens without a backend script.
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Best Aspect Ratio for YouTube Thumbnails
YouTube thumbnails display at 16:9. The recommended pixel size is 1280×720 for sharp results on all devices.
Developer
Create Favicon for Next.js
Next.js 13+ supports app/icon.png and app/favicon.ico. Generate a full icon set from your logo in the browser.
Conversion
Convert PNG to SVG What to Expect
True vectorization of photos is not possible in one click. Our tool embeds the PNG inside SVG for compatible workflows.
Developer
SHA256 vs bcrypt for Passwords
SHA256 is fast which makes it wrong for password storage. bcrypt is slow by design to resist brute force.
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Resize Image to 1080×1080
social posts works best with images at 1080×1080 pixels (1:1 square). Resize before you upload to avoid compression surprises and slow uploads.
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Resize Image to 1920×1080
HD thumbnails and banners works best with images at 1920×1080 pixels (16:9 widescreen). Resize before you upload to avoid compression surprises and slow uploads.