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Take a retina-quality (2x) screenshot in Python with httpx

A default screenshot renders at 1 CSS pixel = 1 image pixel, which looks soft on any modern display and falls apart the moment a designer zooms in. "device_scale": 2 renders the page the way a MacBook does — double density — so text is crisp in decks, docs and social cards.

Below is a complete, runnable Python program using httpx (pip install httpx). It reads your API key from the SNAPDOK_KEY environment variable — free keys take about thirty seconds and need no card.

import os
import httpx

resp = httpx.post(
    "https://snapdok.io/v1/render",
    headers={"Authorization": "Bearer " + os.environ["SNAPDOK_KEY"]},
    json={
        "url": "https://your-app.com/report/42",
        "format": "png",
        "width": 1280,
        "device_scale": 2,
    },
    timeout=90,
)
resp.raise_for_status()

with open("retina.png", "wb") as f:
    f.write(resp.content)

The arithmetic to keep in mind: pixel dimensions are width × device_scale, so 1280 wide at scale 2 produces a 2560-px-wide image with roughly 4× the bytes of the 1× version. For thumbnails that will be displayed small, 1× is cheaper and looks identical after downscaling; spend the scale factor where humans will look closely.

If you arrive from Urlbox or ApiFlash muscle memory: device_scale_factor is accepted as an alias and normalised to the same thing — both spellings even share one cache entry, so mixed codebases do not double-render. JPEG ("format": "jpeg") at scale 2 is often the sweet spot for photography-heavy pages: retina sharpness, a fraction of the PNG size.

Same endpoint, one more trick: if the page you are rendering has a form on it, adding "pdf_forms": true to a PDF render brings it back with real, fillable AcroForm fields — a PDF people can type into, not a picture of one. How that works.

Notes for httpx

httpx looks like requests but differs where it bites: it ships a 5-second default timeout, which a render that drives a real browser will blow through on heavier pages — hence the explicit timeout=90. raise_for_status() exists and behaves the same. If you are on asyncio already, the same call works with httpx.AsyncClient and await client.post(...) — the request body and headers are identical.

Response headers worth reading

HeaderMeaning
X-CacheBoth device_scale spellings hit the same cache entry.
X-RateLimit-RemainingRequests left in the current second.

Full parameter reference: the docs. Hard numbers on caps and timeouts: limits.

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