diff --git a/packages/mosaic/sql/src/transforms/scales.ts b/packages/mosaic/sql/src/transforms/scales.ts
index 49b9ae9d4..eeed09a71 100644
--- a/packages/mosaic/sql/src/transforms/scales.ts
+++ b/packages/mosaic/sql/src/transforms/scales.ts
@@ -88,7 +88,7 @@ function scaleSymlog({ constant = 1 } = {}): ScaleTransform<number> {
   const _ = +constant;
   return {
     apply: x => Math.sign(x) * Math.log1p(Math.abs(x)),
-    invert: x => Math.sign(x) * Math.exp(Math.abs(x) - _),
+    invert: x => Math.sign(x) * (Math.exp(Math.abs(x)) - _),
     sqlApply: c => (c = asNode(c), mul(sign(c), ln(add(_, abs(c))))),
     sqlInvert: c => mul(sign(c), sub(exp(abs(c)), _))
   };
diff --git a/packages/mosaic/sql/test/scales.test.ts b/packages/mosaic/sql/test/scales.test.ts
new file mode 100644
index 000000000..54c61ffdb
--- /dev/null
+++ b/packages/mosaic/sql/test/scales.test.ts
@@ -0,0 +1,11 @@
+import { expect, describe, it } from 'vitest';
+import { scaleTransform } from '../src/index.js';
+
+describe('scaleTransform', () => {
+  it('symlog invert is the inverse of apply', () => {
+    const s = scaleTransform<number>({ type: 'symlog' });
+    for (const x of [5, 10, 100, -7, 1, 0.5]) {
+      expect(s.invert(s.apply(x))).toBeCloseTo(x, 9);
+    }
+  });
+});