remove.bg API is moving to Leonardo: a background removal API

If you call the remove.bg API, the vendor's own page says a change is coming: as of 2026-09-29, remove.bg's API documentation reads "Starting December 1, 2026, background removal moves to Leonardo.Ai, also part of Canva." Check that page before December 1 for the exact steps for your account.

This post does not compare services. It records what remove.bg says, then lists what a replacement call to Sume's RMBG 1.0 looks like, so you can judge the swap yourself. Sume's side comes from the Sume API reference and the API reference docs page, read 2026-09-29.

What does remove.bg say is changing?

Two remove.bg pages carry the news. Both are quoted below as they read on 2026-09-29. Nothing here is a Sume claim.

How do I remove a background with Sume's API instead?

Send a public HTTPS image_url to POST /v1/rmbg-1.0/remove. The job is asynchronous by default. When it completes, the result is a Sume-hosted PNG with an alpha channel, so the removed background is transparent. There is no model field: Sume selects the model.

The depth on this endpoint (modes, webhooks, cancellation) is in Remove background API: transparent PNG cutouts with Sume RMBG 1.0. The short version:

curl -X POST https://api.sume.com/v1/rmbg-1.0/remove \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: rmbg-migration-001" \
  -d '{
    "image_url": "https://example.com/inputs/portrait.png",
    "mode": "async"
  }'

curl https://api.sume.com/v1/jobs/job_123/result \
  -H "Authorization: Bearer $SUME_API_KEY"

What should I check before I switch?

A migration checklist, each item from the RMBG 1.0 contract:

• Input: image_url is a public HTTPS URL. If your current integration sends file bytes, the RMBG 1.0 request has no field for them; host the image at a public HTTPS URL first.
• Output: a PNG with alpha.
• Each request takes one image_url, so a folder of images means one request per image; see Remove background from images in bulk.
• Waiting: sync and subscribe wait at most 30 seconds. For a longer wait, submit with async and poll status_url, or use a webhook that fires when the job completes, fails, or is canceled.
• Already-transparent inputs: when the input has substantial fully transparent pixels, Sume flattens it onto mid-gray #808080 before the provider sees it. It is still one billed removal.

How much does Sume background removal cost?

API pricing lists background removal at $0.0225 per image, plus a 5.5% agent fee by default. Read the current number on that page, not from a blog post, before you budget a bulk run.

If the workspace balance cannot cover the estimated amount, the submit returns 402 and no generation job is started.

What does this post not tell you?

Anything about how remove.bg or Leonardo.Ai will behave after December 1, 2026, beyond the sentences quoted above: pricing, credits, limits, and account rules belong to those vendors' own pages. Sume's docs do not describe a remove.bg-compatible request shape, so plan to change the request body and the way you read results.