What image tools does Texterfly offer?

Texterfly offers 3 free image tools: a Color Palette Generator (extracts HEX, RGB, HSL, CMYK colors from any uploaded image, with eyedropper and CSS export), an Image to Base64 Converter (converts images to data URIs with HTML, CSS, and JSON output), and a Base64 to Image Decoder (decodes Base64 strings back to visible images with download). All are browser-based with no image uploads to servers.

What color formats does the color palette generator output?

The Color Palette Generator outputs four color format codes for each extracted color: HEX (e.g. #3A86FF — used in web CSS and design tools), RGB (e.g. rgb(58, 134, 255) — used in screen design), HSL (e.g. hsl(217, 100%, 61%) — useful for manipulating lightness and saturation), and CMYK (e.g. cmyk(77, 47, 0, 0) — used in print design). You can copy any format with one click.

What is Base64 image encoding?

Base64 image encoding converts binary image data into a string of ASCII characters. The result is a "data URI" — a self-contained text string that browsers can render as an image without fetching an external file. Format: data:image/png;base64, . Base64 increases image size by ~33% but eliminates the need for a separate HTTP request, making it useful for small icons and inline images.

When should I use Image to Base64?

Use Image to Base64 when: embedding small icons directly in CSS (saves one HTTP request), including images in email signatures or HTML newsletters (bypasses email client image blocking), building single-file web applications or offline HTML files, embedding images in JSON API payloads, or adding inline images to SVG files.

What is the difference between HEX, RGB, HSL, and CMYK?

HEX (#RRGGBB) is a 6-digit hexadecimal code used in CSS and most design tools. RGB (red, green, blue) defines colour by mixing three light channels from 0–255. HSL (hue, saturation, lightness) makes it intuitive to create colour variations by adjusting a single value. CMYK (cyan, magenta, yellow, black) is used in print design, defining ink percentages for physical printing. For web design, HEX and RGB are most common. For print, CMYK is required.

What image formats does the Base64 converter support?

The Image to Base64 Converter supports: JPEG (.jpg, .jpeg), PNG (.png), GIF (.gif), SVG (.svg), and WebP (.webp). Each format produces a correctly typed data URI (e.g. data:image/png;base64,... for PNG files).

How does the Base64 to Image Decoder work?

Paste a Base64 string (with or without the data:image/...;base64, prefix) into the decoder. The tool renders the image visually, shows the resolution (width × height in pixels) and decoded file size, and provides a download button. It also detects and helps clean common issues like extra whitespace or line breaks in the Base64 string.

How does the color palette generator extract colors?

The Color Palette Generator uses a colour quantization algorithm (similar to k-means clustering) to analyse pixel data across the uploaded image and identify the most visually dominant and representative colours. You can also use the manual eyedropper tool to click any specific pixel in the image to get its exact colour code.

Are these image tools free?

Yes. All 3 image tools are 100% free with no registration, subscription, or payment required.

Are my images private?

Yes. All image processing runs entirely in your browser using the Canvas API and FileReader. Your images are never uploaded to any server, never stored, and never transmitted. This applies to all three tools including the colour palette generator.

Does this image resizer upload my photos to a server?

No. Everything runs locally in your browser using the HTML5 Canvas API. Your images never leave your device and are never sent to Texterfly's servers.

What image formats does this tool support?

You can upload JPG, PNG, WebP, GIF, and BMP files. You can download as the original format, or convert to JPEG, PNG, or WebP.

Can I resize multiple images at once?

Yes. Drop multiple files onto the upload area. All images are resized with the same settings. Download them individually or all at once as a ZIP file.

Will resizing reduce my image quality?

Downscaling (making an image smaller) produces excellent quality using the Canvas API's high-quality bicubic interpolation. Upscaling (making it larger than the original) will soften the image — a warning is shown when this happens.

How do I resize an image to a specific file size in KB?

Use the JPEG or WebP format with the quality slider. Lower quality = smaller file size. The estimated file size updates live so you can dial in exactly the size you need.

What are the correct social media image sizes?

Instagram square: 1080×1080. Twitter/X header: 1500×500. Facebook cover: 820×312. LinkedIn banner: 1584×396. YouTube thumbnail: 1280×720. OG/meta image: 1200×630. Use the presets in the tool to set these automatically.

Is there a file size limit?

There is no enforced limit — the tool is bounded only by your browser's available RAM. Most images up to 50 MB process instantly. Very large files (100 MB+) may cause a brief pause while loading.

Can I convert a PNG to JPG while resizing?

Yes. Select JPEG from the output format dropdown. The Canvas API converts the image during the resize step, so you get a resized JPEG in one operation.

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Image Resizer Online

Resize images by pixels or percentage, convert format, and download instantly — free, no upload, 100% browser-based.

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Free Image Resizer Online — Resize by Pixels or Percentage, No Upload

Texterfly's Image Resizer resizes any image instantly in your browser using the HTML5 Canvas API — nothing is uploaded to a server, nothing is stored, and there are no file size limits beyond your device's RAM. Drag in a JPG, PNG, WebP, GIF, or BMP and download the resized result in seconds.

Resize by exact pixel dimensions with optional aspect ratio lock, or switch to percentage mode to scale by any factor from 1% to 400%. Convert format in the same step — turn a PNG into a WebP, or a BMP into a JPEG, with a quality slider to control file size. Need to resize ten images at once? Drop them all in, resize in batch, and download as a single ZIP.

Social Media Image Size Guide

Use the presets in the tool for one-click sizing, or reference this table for the correct dimensions on each platform.

Platform	Image Type	Size (px)	Aspect Ratio
Instagram	Square post	1080 × 1080	1:1
Instagram	Portrait post	1080 × 1350	4:5
Twitter / X	Post image	1200 × 675	16:9
Twitter / X	Profile header	1500 × 500	3:1
Facebook	Cover photo	820 × 312	2.63:1
Facebook	Shared post	1200 × 630	1.91:1
LinkedIn	Personal banner	1584 × 396	4:1
LinkedIn	Shared image	1200 × 627	1.91:1
YouTube	Thumbnail	1280 × 720	16:9
Web / SEO	OG meta image	1200 × 630	1.91:1

Features

🔒

No upload — 100% private

The Canvas API processes images locally in your browser. Your photos never leave your device. Works offline after page load.

📐

Pixels or percentage

Switch between exact pixel dimensions and percentage scaling. The aspect ratio lock updates both dimensions in sync.

📱

12 social media presets

One-click presets for Instagram, Twitter, Facebook, LinkedIn, YouTube thumbnails, OG images, and more.

🔄

Format conversion

Convert JPG → WebP, PNG → JPEG, or any combination in the same resize step — no separate converter needed.

🎛️

Quality slider

Control JPEG/WebP compression to balance file size vs. quality. Estimated output size updates live.

📦

Batch + ZIP download

Drop multiple images, resize them all with one click, and download as a single ZIP file.

👁️

Before / after preview

Drag the split divider to compare the original and resized image side by side at any ratio.

⚡

Multi-step downscaling

For large reductions (e.g. 4000px → 200px) the tool uses iterative half-step downscaling for sharper, better results than single-pass Canvas resize.

Frequently Asked Questions

Does this image resizer upload my photos?

No. Everything runs in your browser via the HTML5 Canvas API. Your images are never transmitted to any server. You can verify this by opening DevTools → Network tab — you will see zero network requests when resizing.

How do I resize an image without losing quality?

For downscaling, this tool uses iterative multi-step halving for large reductions, which produces significantly sharper results than a single-pass resize. Use PNG output for lossless results. For upscaling, no software can recover detail that wasn't in the original — the result will be softer.

How do I reduce an image file size to under 1 MB or 500 KB?

Select JPEG or WebP as the output format and reduce the quality slider. WebP gives better compression than JPEG at the same visual quality. The estimated file size shown after resizing helps you dial in the target.

Can I resize a PNG without a white background appearing?

Yes. Keep the output format as PNG (or WebP). JPEG does not support transparency — if you convert a transparent PNG to JPEG, the transparent areas become white. Use PNG or WebP to preserve the alpha channel.

Is there a file size or resolution limit?

No hard limit — the tool is bounded only by your browser's available RAM. Images up to 50 MP process without issue on modern devices. Very large RAW-equivalent files may cause a brief pause.

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