Make your logo emit real HDR light
Upload a brand mark and encode it as a genuine HDR asset. On a capable display it renders above ordinary white — no halo painted around it, and no change to the artwork.
- Works on PNG, SVG and JPEG, with transparency preserved
- Brand-safe mode keeps your exact colour
- Export for LinkedIn, for your own site, or as an SDR fallback
- Free, no watermark, nothing uploaded
This is a free online HDR logo maker. It takes an ordinary logo file and re-encodes the parts you choose as a genuine Rec.2100 PQ image, so on a display with headroom those pixels emit more light than the white of the page around them. The artwork itself is untouched — no halo is drawn, no glow is painted, and the shape you upload is the shape you get back. White highlights are detected automatically, or you can select any brand colour and glow only that. Export to JPEG, HDR PNG, or an SDR fallback. No account, no watermark.
Free, with no account and no watermark. Your image is processed in your browser and never uploaded — read how HDR glow works.
Four ways to glow a mark
The same engine, pointed at different priorities. Most logos need only the first.
White Auto Glow
The default. Near-neutral regions are found perceptually, so an off-white wordmark is detected while a pale background is not. Nothing to configure.
Any Color
Pick a brand colour from the detected palette or sample it off the artwork. Only that colour lights up, everywhere it appears or in one region.
Brand Safe
Preserve mode caps brightness at the point where your colour would have to change. The chromaticity comes through untouched, so the mark stays on-brand.
Maximum Glow
Takes the full brightness you ask for and spends saturation to get there. Right for a mark that should read as light first and colour second.
Why a logo is the ideal subject
HDR encoding is unforgiving of smooth gradients in 8-bit files. Near the top of the PQ curve, adjacent code values are far apart in luminance, so a soft sky bands where a solid shape does not.
A logo is the opposite of a difficult case: flat areas of colour, hard edges, and a small bright region against a larger dark one. That last part matters more than it sounds — displays reach their highest peak brightness on small areas, so a wordmark covering a few percent of the frame can be driven far harder than a full-frame wash.
What to watch for
- If more than about a third of the frame glows, most displays will tone the whole thing back down. The editor warns you when coverage gets there.
- JPEG artefacts around a white mark carry faint colour tints. Those get amplified along with the signal, so the near-white core is neutralised before it is brightened.
- Very thin strokes at small sizes lose the effect to anti-aliasing — the edge pixels are only partly selected, which is correct but reduces the visible area.
Questions
What file should I upload?
A PNG, SVG or JPEG works. Vector and flat raster logos give the best results because the effect is strongest on solid shapes with hard edges. SVG is rasterised at a generous resolution and sanitised before anything is drawn.
My logo is on a transparent background — is that fine?
Yes. Both PNG exports keep the alpha channel intact and add no background. JPEG has no alpha channel at all, so if you export for LinkedIn you choose a black or white matte and the edges are composited in linear light.
Can I glow the mark and the wordmark differently?
Yes. Each is a separate layer with its own brightness and colour behaviour. A common setup is white wordmark at full strength with the coloured mark slightly lower, so the type leads.
Will this change my logo’s colours?
Not in Preserve mode — brightness stops before the colour would shift. In Balanced and Max glow it will, deliberately, and the panel shows exactly how much saturation is being spent.
What resolution should I work at?
Whatever your original is. Analysis runs on a downsampled copy for speed, but every export re-renders from the full-resolution original — never from the preview.
What are the numbers?
Every figure below is either a published constant or a value this tool computes. None is an estimate, and each one is traceable to the standard beside it.
| Measurement | Value | Source |
|---|---|---|
| Diffuse white reference | 203 nits | ITU-R BT.2408 |
| PQ maximum | 10,000 nits | SMPTE ST 2084 |
| 8-bit PQ code for diffuse white | 148 | Computed |
| 8-bit PQ code for 1,600 nits | 205 | Computed |
| Rec.2020 white ceiling | 10,000 nits | Computed |
| Rec.2020 green ceiling | 6,780 nits | Computed |
| Rec.2020 red ceiling | 2,627 nits | Computed |
| Rec.2020 blue ceiling | 593 nits | Computed |
| Blue's share of Rec.2020 luminance | about 6% | Computed |
| LinkedIn logo size | 400 × 400 px | Measured |
| LinkedIn post and ad size | 1200 × 627 px | Measured |
| LinkedIn JPEG re-encode | quality 90, 4:4:4 | Measured |
| Price | Free, no account | This site |
Where do these figures come from?
This tool implements published standards rather than an in-house approximation of them. Each specification below defines part of what the exported files contain.
- ITU-R BT.2100
Defines the HDR system this tool encodes into — BT.2020 primaries with the PQ transfer function.
- ITU-R BT.2408
Sets diffuse white at 203 nits, which is the reference every brightness figure here is measured against.
- SMPTE ST 2084
The PQ transfer function itself: absolute luminance from 0 to 10,000 cd/m², independent of display.
- ITU-T H.273
The code points behind cICP 9 16 0 1 — colour primaries, transfer characteristics, matrix and range.
- W3C PNG Third Edition
Specifies the PNG cICP chunk, which is how an HDR PNG declares itself without an ICC profile.