ConvertPic - Image Converter: HEIC, JPG, PNG, WEBP
ConvertPic turns an image from one file format into another without installing anything. Open a picture, choose the format you need (JPG, PNG, WEBP, GIF, BMP, TIFF or PDF), adjust the quality, optionally make it smaller, and download the result.
It is handy whenever a website, form or program refuses the file you have: a portal that only accepts JPG, a print shop that wants a PDF, an old tool that needs BMP, or a blog where a lighter WEBP would load faster. You can also resize a photo to fit common social media sizes before posting it.
Everything happens inside your browser on your own device. The images are read, converted and handed back to you as downloads; they are not sent to a server and there is no account to create.
The app runs entirely in your browser. What you enter is saved only on this device.
How to use ConvertPic
- Select your images. Tap the large Select Images area and choose a source: pick one image, several images (up to five at a time), or import from your files. JPG, PNG, WEBP, GIF and BMP are supported in every modern browser; TIFF and HEIC depend on what your browser can open.
- Check the preview. The conversion screen shows the picture with its original format, pixel size and file size so you know what you are starting from.
- Choose an output format. Tap one of the format chips. JPG and WEBP are compact for photos, PNG keeps sharp edges and transparency, PDF wraps the image in a single page, and GIF, BMP and TIFF are there for programs that need them.
- Set the quality. For JPG and WEBP, move the quality slider. Lower values give smaller files; the estimated output size updates as you drag so you can aim for an upload limit.
- Resize if needed. Turn on Resize for a single image and enter a width or height in pixels, pick 25, 50 or 75 percent, or tap a preset such as IG Post (1080x1080), IG Story (1080x1920), X / Twitter, FB Post or YT Thumb. Keep the aspect-ratio lock on to avoid stretching.
- Convert and download. Tap Convert. The result screen compares the old and new file sizes. Use Save to download the file, Save All after converting several images, or Share if your browser offers a share sheet.
Features
- Converts to JPG, PNG, WEBP, GIF, BMP, TIFF and PDF
- Reads JPG, PNG, WEBP, GIF, BMP and TIFF; HEIC works in browsers that can open it, such as Safari
- Quality slider for JPG and WEBP with a live estimate of the output size
- Resize by pixels or percentage, with an aspect-ratio lock
- Social media size presets for Instagram, X, Facebook and YouTube thumbnails
- Convert up to five images in one go
- Before-and-after file size comparison
- Default output format and quality are remembered in this browser
- Interface in many languages
Choosing the right image format
Lossy versus lossless
Image formats fall into two families. Lossy formats such as JPG and WEBP throw away detail the eye is unlikely to notice, which makes photos dramatically smaller. Lossless formats such as PNG, BMP, TIFF and GIF keep every pixel exactly, so files are larger but nothing degrades.
A practical rule: use a lossy format for photographs and a lossless one for screenshots, logos, diagrams and anything with text or flat colour. Saving a screenshot as JPG often produces fuzzy halos around letters, while saving a holiday photo as PNG can make it five to ten times bigger than necessary.
What the quality setting really does
The JPG and WEBP quality number is not a percentage of the original; it controls how aggressively fine detail is simplified. Values around 80 to 90 usually look identical to the original at normal viewing size, while values below about 60 start to show blocky areas in skies and soft gradients.
Each time a JPG is re-saved, a little more detail is lost. If you expect to edit an image several times, keep a lossless master copy (PNG or TIFF) and export a JPG only at the end.
Transparency and colour
PNG, WEBP and GIF can store transparent areas; JPG, BMP and most TIFF files cannot. When you convert a transparent logo to JPG, the transparent parts must be filled with a solid colour. GIF is limited to 256 colours, which suits simple graphics but makes photos look grainy or banded.
Resolution versus file size
File size depends mostly on the number of pixels. Halving both the width and height leaves a quarter of the pixels, so resizing a 4000-pixel-wide camera photo to 1080 pixels often matters far more than lowering the quality. Social networks resize uploads anyway, so sending an image at their preferred size avoids a second round of compression on their side.
Common targets are 1080x1080 for a square Instagram post, 1080x1920 for stories, around 1200x675 for X and 1200x630 for Facebook link images, and 1280x720 for YouTube thumbnails.
When to use PDF, TIFF or BMP
PDF is useful when a form or email recipient asks for a document rather than a picture, for example a scanned receipt or ID page. TIFF is common in printing and archiving workflows. BMP is mainly needed by older Windows software and some embedded devices; it is uncompressed and therefore large.
Frequently asked questions
Are my images uploaded to a server?
No. The images are decoded, converted and encoded inside your browser on your device, and the results are offered as downloads. No account is needed.
What is saved in my browser?
Only your preferred default output format and quality, stored in this browser's local storage. The images themselves are kept in memory just while the page is open and disappear when you reload or close it. Clearing your browser data also resets the settings.
Why can't I open a HEIC photo?
HEIC is the iPhone camera format. The web version relies on the browser to read it, and at the moment mainly Safari can. In other browsers, export the photo as JPG first or use the phone app, which converts HEIC directly.
Can I convert a PDF into an image?
Not in the web version. You can turn images into a one-page PDF, but reading PDFs as input is only available in the iPhone and Android app.
Why is WEBP export not working in my browser?
WEBP export uses the browser's own encoder. Chrome, Edge and Firefox support it; some versions of Safari do not and will show an error. Pick JPG or PNG instead, or try another browser.
Can I resize several images at once?
The web version converts up to five images in one batch, but resizing is applied only when you convert a single image. Unlimited batches and batch resizing are features of the phone app's Premium option.
How is the web version different from the phone app?
The phone app can save straight to your photo library, read HEIC and PDF files on any device and offers Premium batch features. The web version downloads files instead and covers the everyday conversions without installing anything.
Limitations of the web version
- Converted files are downloaded rather than saved to a photo library
- PDF files cannot be used as input on the web
- HEIC and TIFF input depends on the browser (HEIC mainly in Safari)
- WEBP export is unavailable in browsers that cannot encode WEBP
- Batches are limited to five images and resizing applies to single images only
- Very large images may be slow on older devices because processing runs locally
Phone app
ConvertPic is also available as an app for phones and tablets: