Why is my SVG
bigger than my PNG?
Vectorising an image does not make it lighter. It makes it scale without going soft and editable in a vector program. The weight goes the other way, and by a lot.
Short answer: because an SVG is not a compressed format — it is a text file full of coordinates. Our 900×600 photo was 98,186 bytes as a PNG and came out between 171,863 and 2,707,193 bytes as an SVG, depending on the setting: 1.8× to 27.6× the original. The high-detail setting produced 8,251 separate shapes. An SVG is still the right answer when you need it to scale without going soft or to be edited in Illustrator or Figma.
Written by the Tool Pantry team on 22 October 2026. Every number comes from tracing with the same engine the site uses, then measuring the output: bytes, shape count, colour count and time. One more thing the measurements turned up: the generated SVG contained no text elements at all, which is why we have a section on what that does to a logo.
What the conversion actually does
The tool runs a curve tracer: it walks the image, groups neighbouring pixels of similar colour, and turns each group into a vector shape. Straight edges become straight lines and smooth gradients become flat patches of colour.
The result is a real SVG file: it scales without going soft, and you can open it in Illustrator, Inkscape or Figma and edit it. What it does not do is reconstruct the photograph. The photo was a grid of pixels; the SVG is a list of flat areas.
The first surprise: the SVG is heavier than the PNG
An SVG is not a compressed format. It is a text file full of coordinates, so vectorising an image and expecting a smaller file is the most common mistake there is. We measured it with the same tracer the tool uses:
| Setting | SVG size | Against the PNG | Shapes | Time |
|---|---|---|---|---|
| Low · 16 colours | 455,801 bytes | 4.6× | 1,673 | 232 ms |
| Low · 4 colours | 171,863 bytes | 1.8× | 317 | 81 ms |
| Medium · 16 colours | 982,262 bytes | 10.0× | 3,709 | 225 ms |
| Medium · 4 colours | 376,861 bytes | 3.8× | 639 | 134 ms |
| High · 16 colours | 2,707,193 bytes | 27.6× | 8,251 | 634 ms |
| High · 4 colours | 1,049,376 bytes | 10.7× | 1,408 | 461 ms |
No setting lands below the PNG. More detail means a bigger file: the high-detail setting with 16 colours multiplies the weight by 27 and produces 8,251 separate shapes.
Line art behaves differently. A 900×600 drawing was 6,031 bytes as a PNG and 21,909 bytes as an SVG with only 140 shapes — still heavier, but for a different reason: the SVG is no longer a photo with blotches, it is a short list of outlines.
The control that matters most: the number of colours
Dropping the palette from 16 colours to 4 is the change that removes the most weight. On the photo, the medium setting went from 982,262 to 376,861 bytes and from 3,709 shapes to 639. The same picture with fewer shades — closer to a screen print than to a photograph.
If the image already has few colours, the number does nothing: our line-art drawing produced exactly the same 140 shapes whether we asked for 3 or 4 colours.
The text in the image stops being text
In our measurements the generated SVG contained not a single text element — no selector, no searchable word. Everything is curves.
Two practical consequences:
- A logo with words in it (a TOY SHOP sign, a brand name) becomes a silhouette. It looks identical, but it can no longer be searched, translated, or have a typo fixed.
- The SVG gets much bigger for a specific reason: every letter is drawn as an outline, with dozens of points.
When it is the right tool
| If you want… | Use |
|---|---|
| A logo or illustration to print large | Image to SVG — it scales without going soft |
| An icon for a site, sharp at any size | SVG, or the reverse conversion if you need a bitmap |
| A photograph for a web page | Compress the image — an SVG of a photo weighs ten times more |
| A photo whose text has to stay searchable | Neither PNG nor SVG: the text has to remain text |
The limits, plainly
- No image is embedded in the SVG. It is pure tracing; the photo is not tucked inside.
- A photo does not turn into a drawing. It comes out as a mosaic of flat patches, which is the opposite of what most people expect from “convert to vector”.
- The file grows. From 1.8× to 27.6× the weight of the PNG, depending on the setting.
- Text stops being text and letters stop being editable.
- The result depends on the source. It works beautifully on line art and flat shapes; smooth gradients show their steps.
How do I convert an image to SVG?
Open the image to SVG converter, choose the detail level and the number of colours, and press Trace. The tracer runs in your browser: the image is never uploaded.
Is the SVG smaller than the PNG?
In our measurements, never. A 900×600 photo (98,186 bytes as a PNG) came out between 171,863 and 2,707,193 bytes depending on the setting, which is 1.8× to 27.6× the original. SVG is not a compressed format.
Why does a traced photo look blotchy?
Because the tracer groups similar pixels into flat patches of colour. A photo has thousands of different tones in every area; vectorising turns each area into one colour. At 4 colours it looks like a screen print; at 16 it is closer to the original, but the file grows sharply.
Can I edit the text that came out of the image?
No. Text in the image becomes curves and stops being text — in our tests the generated SVG had not a single text element. It looks the same, but it cannot be searched or edited.
Which detail setting should I use?
The highest one for a logo or a drawing, with 4 colours if you want a light file. For a photograph it is not worth it: the weight multiplies and the result still looks like a photo.
Is my image uploaded anywhere?
No. The tracer runs inside your browser and the SVG is downloaded from the same tab.